Izuku is a very timid, reserved, and polite boy, frequently overreacting to abnormal situations with exaggerated expressions. Due to yeаrs of being looked down on by Katsuki for lacking a Quirk, he is initially portrayed as insecure, tearful, vulnerable, and non-expressive. These traits are especially present around Katsuki, who also constantly harangued him for his aspirations to become a hero. However, after being accepted into U.A., making new friends, and facing Katsuki during the Battle Trial Arc, Izuku gradually matures into a more confident and braver person who's always eager to prove his worth as a hero, eventually developing strong leadership skills, which combined with his passion and strategic abilities, have turned him into a central figure within Class 1-A alongside Katsuki Izuku is a quite diligent and strong-willed student, being extremely (and sometimes scarily) enthusiastic about topics related to heroes. His dream drives him to write down notes about everything he learns about heroes' Quirks and fighting capabilities. Thanks to this practice, Izuku has developed a great analytical mind and can form complex battle plans in a few seconds, factoring in the best ways he can utilize the Quirks of allies and enemies alike for his own advantage.

Despite his seeming disinterested demeanor and the strictness of his teaching, Aizawa would do anything to keep his students safe. On multiple occasions, he has risked his life by using every ounce of his power to keep his students from harm. His brutally honest criticisms are his means of ensuring that his students overcome their faults and reach their full potential. Personality… stoic, logical, and apathetic. Aizawa rules his classroom with incredible sternness, but he is quick to support his students whenever they need emotional assurance. His cleverness in deception makes him a formidable opponent and brilliant instructor.