Lee is unable to use any type of ninjutsu or genjutsu. His fellow students teased him for this handicap while he was in the Academy (calling him a "hot-blooded dropout"), though Lee ignored their words and began specializing in taijutsu, hoping to become a powerful ninja despite his inability to use standard ninja techniques. Upon being assigned to Guy's team, Guy took a personal interest in Lee's attempts to prove himself and began to help him in his dream of excelling in taijutsu. With Guy's assistance Lee learned many advanced taijutsu abilities, bringing him ever closer to achieving his oft-declared goal of becoming a splendid ninja.
Lee is known for speaking respectfully to others, being very proper in both English and Japanese versions. In the Japanese anime and manga, he always utilizes honorifics such as "san and "kun"; in the English adaptations, he never uses contractions. His relationship with Guy has also caused him to acquire many of Guy's traits. Lee's green jumpsuit and shiny mop-top haircut, having already had Guy's distinctive thick eyebrows (leading to the nickname of "Bushy Brow" or "Fuzzy Eyebrows"), are direct results of his modeling himself in his sensei's image. Guy's influence has also caused the reshaping of Lee's personality, and his dedication to his promises.
Lee has a number of other odd personality traits, though whether or not they are results of Guy's mentorship is unknown. He also has a keen sense of honor and respects his opponents, refusing to hold grudges against those who have defeated him and returning favors to those that have helped him. His attempts to prove and better himself are recurring themes for his actions throughout the series. He is generally optimistic and believes that with hard work and passion, he can surpass a natural genius, but can be prone to depression when faced with setbacks. His drive to succeed is initially most evident with his rivalry with Neji, having learned from Guy that having a rival will provide incentive to succeed.
Shortly after his introduction, Lee reveals that he likes Sakura, asking her to be his girlfriend and vowing to protect her immediately after they meet. While she does not seem to share these feelings for him and considers him weird, Lee maintains these feelings throughout the Chunin Exams. At one point, he comes to her rescue, against three to one odds and uses forbidden techniques in an attempt to protect her, considering her someone dear to him. She continues to refer to him by the more formal "Lee-san", as opposed to "Lee-kun".
Guy's leadership has also influenced Lee's training habits, which, coupled with his hard-working resolve, has allowed Lee to rapidly improve. When making a promise, for example, Lee assigns himself arduous tasks to complete in the event that he doesn't provide. Since Guy began training him, Lee has worn heavy weights on his ankles, increasing his strength at the cost of inhibiting his speed to levels that his peers still consider quite fast. Upon removing the weights, Lee's speed vastly increases, making it almost impossible to see his movements with the unaided eye.
Through Guy's teachings, Lee has learned many powerful taijutsu techniques. The most basic of these is his Strong Fist style of combat, a martial art style focusing on external damage. Lee has also learned how to open the first five of the eight chakra gates, a feat that is difficult for even the most talented ninja. Lee has also learned or developed a number of taijutsu techniques that take advantage of the extreme power and speed he gains from opening chakra gates. Lee has manifested a natural predisposition towards the Drunken Fist (酔拳, Suiken?, English TV: "Loopy Fist"), a unique battle style that can't be learned or taught and is reminiscent of the actual Zui Quan martial art. When he drinks as little as one drop of alcohol, he becomes inebriated and rude, as well as an unpredictable fighter. His alcoholic lapses are relatively brief, and he has no memory of his actions once he has returned to his normal self