Yun's physical appearance is much different to his twin brother Yang. In comparison, Yun has long brown hair, braided into a pony tail, and wears a blue baseball cap with a yellow visor and a circle shape with a skateboard on his head, a sleeveless, white Chinese martial arts shirt with a yellow hem and blue trims and buttons, yellow wristbands with finger-less gloves on his arms, and black/dark blue pants and sneakers with yellow and white outlines. If Yun is not fighting his opponents, he really rides on his skateboard.
Yun is described as more energetic and extroverted one of the Lee Brothers, who taught Kung Fu. He is actually playful, upbeat, and easygoing like Yang. While the confidence is going on, his personality is not as cocky or sharply mouthed as Yang, though he is not above cackling jokes at the expense of other opponents he beats. Also, he is said to be impulsive and a born leader. Alongside Yang, when Yun interestingly became enthusiast of watching movies as he seen and idolized Fei Long as a martial arts film star in the events of Super Street Fighter IV: Arcade Edition, he requests in one of his win quotes whether he is so-called "the real Fei Long" and then wants to have a conversation with Yang about meeting him.
Powers and abilities
For the Lee Brothers, Yun has trained the Chinese martial arts based on either Bājíquán or "Eight-Extremities Fist" and Kung Fu as his fighting styles similar to their uncle.