Shortly after his birth, Yamato was abducted by Orochimaru and became one of sixty infants that became test subjects of the latter. They were injected with the First Hokage's DNA in the hopes that they could replicate the First's ability to use Wood Release techniques, as well as an unquantified ability to control tailed beasts. Orochimaru was forced to flee Konoha before he could finish his experimentation, but believed that all of his test subjects had died.
Yamato, however, was the lone survivor, and found himself endowed with the First's abilities. Yamato would graduate from the Ninja Academy and become a Chunin at the age of six. He later joined the ANBU, and, for a time, served under the guidance of Kakashi Hatake. Yamato would also come to have the best performance record of any ANBU serving under the Third Hokage, leading the Third's successor, Tsunade, to have the utmost confidence in Yamato.
Like other ANBU members, Yamato projects a calm, stoic demeanor in stressful situations. Despite this, he can also be quite laid back when not on duty, and is not above using his Wood Release techniques for creating comforts, such as making a house to "camp out" in. While he has been good-natured so far, Yamato claims to be a different sort of leader than Kakashi, one who is not above "ruling by the use of terror" when his team misbehaves. Aside from his obviously intimidating skills as a ninja, however, this "terror" has so far primarily consisted of casting a creepy "ghoul-eyes" expression at his charges, which seems more humorous than terrifying. Naruto, however, is easily creeped out by it, and stated that it felt like Yamato was controlling him with fear.
Yamato is somewhat reluctant to pay for things unless he has to, as he initially protested at having to pay for lunch at Ichiraku Ramen Bar, stating that Kakashi should pay, being the senior ninja, but was flattered into paying when Kakashi said he considered Yamato an equal.
Sasuke and Sai arc
Yamato was assigned to lead Team 7 in meeting with one of Sasori's spies within Orochimaru's ranks. Naruto and Sakura found it difficult to work with their newest team member, Sai, and much of Yamato's time was spent trying to get them to cooperate. Upon arriving at the arranged meeting place, Yamato went ahead dressed as Sasori, to make meeting with the spy easier. After the spy arrived, who turned out to be Kabuto Yakushi, Yamato was able to learn a great deal of information until Orochimaru showed up. Just as Yamato started to contemplate how he would fight Orochimaru whilst keeping up his act as Sasori, Kabuto cut off the head of the Sasori costume, having hoped to kill the real Sasori.
Faced with a combined attack from Kabuto and Orochimaru, Yamato created a wood clone to escape, causing Orochimaru to realize that one of his test subjects had survived. A battle between Orochimaru and Naruto ensued, and Yamato spent much of his time protecting Sakura. When the battle was over, Sai was found to be missing, although a wood clone that Yamato had had following Sai revealed that the latter had joined with Orochimaru. As the clone followed Sai to Orochimaru's hideout, the rest of Team 7 followed the clone. Once they arrived, Yamato used his Wood Release abilities to infiltrate the base. When they eventually fond Sai, they restrained him, and were able to learn about Sai's real mission: to join forces with Orochimaru on behalf of his organization, Foundation, in an attempt to destroy Konoha.
Sai was eventually freed by Kabuto, who in turn was restrained by Sai. Sai, touched by Naruto's words about Sasuke Uchiha, rejoined Team 7 in their other mission of retrieving Sasuke. When the group split up again, Yamato discovered a bingo book whilst going through some of Sai's belongings. In doing so, Yamato learnt that Sai once again had an ulterior motive: to kill Sasuke Uchiha. In desperation, Team 7 went looking for Sai, hoping to stop him from fulfilling his mission. Sai, however, had actually had a change of heart, and attempted to convince Sasuke to come back to Konoha on Naruto's behalf. Due to Sasuke's exponential growth in fighting abilities, however, Sai was no match for him.
Due to an explosive attack from Sasuke, Team 7 was able to find Sai and learn that he had really allied with them. Upon failing to persuade Sasuke to return to Konoha, the team decided to use force instead. Sasuke's growth, however, was too much for the four's joint effort, and he was able to repel them all. After a brief confrontation between Naruto and Sasuke, Yamato attempted to capture Sasuke with his Wood Release: Wood Locking Wall, although Sasuke was able to escape. As an answer to this, Yamato declared that he had no intention of getting too rough on him in front of Naruto and Sakura, but had no choice. Despite this, Sasuke prepared what appeared to be a finishing move. Orochimaru and a freed Kabuto arrived to stop him, however, and they disappeared, leaving Team 7 defeated and unsuccessful in ther mission.
Fire Temple arc
In the anime, Yamato led Team 7 on a mission to the Fire Temple. Upon arrival, Chiriku informed them that the tombs belonging to a former member of the Twelve Guardian Ninja had been robbed of its corpse. While Yamato pondered the motive for this, word reached them which had reached the Fire Temple that the graves of three other former Ninja Guardian members had also had their corpses stolen. Yamato, his team, and Chiriku went to investigate and find the four coffins. While Yamato knew it was clearly some sort of trap, he knew they had no choice but to play along if they wished to retrieve the bodies.
As they neared the coffins, the trap was sprung, and the team became trapped in a rocky cavern. While searching for the way out whilst dodging more traps, Yamato was approached by one of the thieves, Fudo. Caught off guard and completely unprepared for an opponent such as this, Yamato was overpowered by Fudo's unique earth-jutsu prowess and indestructible body, forcing him on the defensive. Eventually, Fudo caught him in a rock-crushing jutsu, but deceived Fudo by merging with the rocks. Yamato regrouped with his team and, having failed to recover the stolen corpses or capture the tomb robbers, returned to Konoha with Sora.
Later, when the tomb robbers emerged again to attack Konoha, Yamato was one of the few Jonin still available to defend the village. He was then sent out to stop one of the resurrected Ninja Guardians from completing the Limelight jutsu, but was intercepted by Fudo. After feeling out Fudo's attack patterns, Yamato used Fudo's blunt attack methods to set up the area for a water jutsu to trap Fudo in mud. He then proceeded to finished off Fudo by crushing him with a wood-jutsu. He went to join Asuma and the others in stopping the bandits' leader, Furido, who released Sora's Nine-Tailed Demon Fox chakra. Because Yamato's wood release was not as refined as the First Hokage's, he couldn't suppress Sora's spliced demon chakra. Yamato instead used his wood jutsu to protect his allies from Sora's attacks.
Hidan and Kakuzu arc
Kakashi recruited Yamato to help with Naruto's training in creating a new jutsu. In addition to being able to create training devices for Naruto with his Wood Release abilities, Yamato was also able to subdue Naruto if he lost control of the Nine-Tails' chakra. Once Naruto completed the initial stages of his training, he moved onto perfecting his pre-existing Rasengan. Kakashi, however, was not able to oversee Naruto in these final stages, due to his volunteering to help Team 10 in the fight against Akatsuki. As such, he left Yamato in charge of the jutsu's perfection. Yamato was able to give advice in the jutsu's creation, and eventually bore witness to the fruits of Naruto's training.
Once Naruto had perfected his jutsu enough to be used in battle, Yamato, Naruto, and the rest of Team 7 joined Kakashi and Team 10. After teaming up with Naruto to stop an attack by Kakuzu, Yamato convinced Kakashi to allow Naruto to fight Kakuzu alone. Once Naruto was successful in defeating Kakuzu, Yamato joined everyone else in returning to Konoha.
Three-Tails Arrival arc
In the anime, Team Kakashi was sent to provide back-up for Team 8 and Kakashi. When they located the team, Yamato assisted in rescuing Hinata. They pursued the opposing Team Guren to a lake, where they located the Three-Tailed Beast. The two teams shifted objectives and, once back-up from Konoha arrived, began trying to seal the beast. Yamato was put in charge of a team meant to stop any attempted interference, but ultimately proved unsuccessful. He made a hideout for the teams to regroup in, and later facilitated in Naruto's rescue from the Three-Tails. After another failed sealing attempt, Yamato returned to Konoha with the others.
Hunt for Itachi arc
When Kakashi received permission from Tsunade to lead a special team to capture Itachi Uchiha in order to bait Sasuke, Yamato joined him as acting head of Team 8, with the pregnant Kurenai remaining behind in the village. Following a confrontation with Sasuke's cohorts in Hebi and members of the Akatsuki, the group was forced to abandon the mission and return to Konoha.
Invasion of Pain arc
When the invasion began, Yamato was away on a mission with Sai and Anko Mitarashi, trying to locate and capture Kabuto. Just when they located Kabuto, Yamato detected that Naruto had broken the seal he had placed on the First Hokage's Necklace, and was about to completely release the Nine-Tails. He rushed back to Konoha to try and stop Naruto, but Naruto was able to come to his senses through other means. He was later seen using his Wood Release to help rebuild Konoha.
Five Kage Summit arc
Yamato refused to let Naruto go to the meeting to talk to the Raikage. Naruto then said he had met his father, and he told him about Madara Uchiha being behind the Nine-Tails attack 16 years ago. Kakashi decided that he and Yamato (much to the latter's surprise) would escort Naruto there. Yamato used one of his Wood Clone Seeds to track Team Samui, so that Kakashi, Naruto and him could follow them to the meeting.
As a Jonin, and a temporarily relieved member of the ANBU, Yamato is highly proficient in multiple areas of shinobi combat, including tracking and trapping. During his test of his new team's skills, he demonstrated considerable ability in taijutsu, and clever use of diversionary tactics. Also, thanks to his training as an ANBU Black Ops, Yamato has keen instincts in battle, allowing him to quickly react to threats.
Wood Element Techniques
Sharing the same DNA as the First Hokage, Yamato possesses the First's signature Wood Release kekkei genkai. The kekkei genkai allows him to use Earth Release and Water Release jutsu. Although he uses the types infrequently, he has proven to be skilled with both. His more common application of earth and water is combining the two to generate living plants and trees which can be manipulated in countless ways. These trees can be grown not only from the earth and pre-existing flora, but from his own body as well, transforming the actual cells into a different form of life.
In addition to simple binding techniques, Yamato has demonstrated multiple unique uses of Wood Release. One such example is his special Transformation Technique known as Wood Release: Transformation, in which Yamato covers his entire body with a wood imitation rather than using an illusion to mask his appearance. Perhaps his most often used technique is the Wood Clone Technique, a clone of him made with wood generated from his body. Because they share the same cells, Yamato is able to track its location, communicate with it at long distances, and absorb any information it has gathered by laying his hand on it. A less battle-oriented use of his kekkei genkai is Yamato's ability to generate wooden structures almost instantly, which he makes use of for his Wood Release: Four Pillars Prison Technique, a large cage used to hold prisoners and intimidate unruly subordinates, and the Wood Release: Four Pillars House Technique, a large house that can be erected at a moment's notice instead of setting up a camp.
However, as the technique was not originally his, Yamato has found that his Wood Release was nowhere near as powerful as Hashirama's in terms of raw power.
Tailed Beast Suppression
Using the First Hokage's special necklace to amplify his powers, Yamato can suppress the power of a tailed beast. It is because of this legendary ability that Hashirama Senju was made Hokage in the first place, and it was greatly coveted by Orochimaru. Although the First Hokage could suppress entire tailed beasts, Yamato has admitted to not being as strong as the original, so it is unknown what the limits of his suppression ability are. However, he was able to suppress Naruto's four-tailed transformation in seconds. He also added a seal to the Hokage's necklace that would activate when Naruto called upon too much of the Nine-Tails' chakra, attempting to restrain him and alerting Yamato to what was happening.