Chan Siu-bak, courtesy name Siu-bak, art-named Kwai-shek, was a Chinese revolutionary from Xinhui, Guangdong. He was one of the Four Bandits, together with Sun Yat-sen, Yau Lit and Yeung Hok-ling.
Photograph at the Hong Kong College of Medicine for Chinese (from left to right: Yeung Hok-ling, Sun Yat-sen, Chan Siu-bak and Yau Lit). The one standing was Kwan King-leung.