Cheung Yat-Ngok was a Chinese-American triad gangster who was affiliated with the Long Zii Tong in Chinatown, San Francisco during the 1870s. In 1878, he and three other Long Zii hatchetmen were sent to hunt down the new arrival Ah Sahm at Ah Toy's brothel after he asked for their boss Xiaojing, but Ah Sahm beat down the four men when they attempted to kidnap him.