Obito is a member of the Uchiha clan, however his personality is much more kind hearted than other known Uchihas and had a tendency to be late and even cry. He was a member of Yondaime's genin team with Rin and Kakashi. At that age, Kakashi was stern and serious, because of this the two bickered and fought alot because of their conflicting personalities.

The team was sent to destroy a bridge that was feeding supplies to an army of enemy Rock ninja that were preparing to attack the Grass village, however they were ambushed and the Rock ninja captured Rin. Obito was in love with Rin and wanted to go after them, but Kakashi, appointed leader by Minato, refused. He knew that the Rock ninja captured her so that they'd get side-tracked off their mission and said that they have to destroy the bridge, and that a ninja that doesn't follow the rules is trash. Obito was distraught and took his anger out on Kakashi, punching him in the face proclaiming that it's true that a ninja that doesn't follow the rules is trash, but a ninja that doesn't care about their teammates is worst than trash and then took off after Rin.

Obito caught up to some Rock ninja and was attacked but Kakashi appeared and saved Obito, but he himself was ambushed by one of the Rock ninja who was using a chameleon-like technique called "Camouflage Concealment," who cut Kakashi's left eye, but Obito's sharingan activated for the first time and was able to see the Rock ninja and kill him. They then caught up to Rin who was caught in a genjutsu by the last Rock ninja that was trying to fish information out of her. Obito and Kakashi disposed of the ninja and freed Rin, however the Rock ninja was still alive and used a technique to cause rocks to fall on the trio, Obito sacrificed himself to push Rin and Kakashi out of the way. After being partially crushed, Obito blamed himself for Kakashi's eye and joked that he never got Kakashi a present for becoming a jonin, then told Rin, the medical specialist, to transplant his left sharingan eye into Kakashi. Kakashi emerged with Obito's sharingan and killed the enemy, but more Rock ninjas appeared and attempted to crush them with more rocks. Rin and Kakashi escaped but Obito was completely covered in rocks.