Ho began photographing at a very young age with a Brownie which his father had left at home, and later with a Rolleiflex twin-lens reflex camera his father gave him at the age of 14. Largely self-taught, his photos display a fascination with urban life, explored alleys, slums, markets and streets. Much of his work consists of candid photographs of the street vendors and children only a few years younger than himself. He developed his images in the family bathtub and soon had built up a significant body of work, chronicling Hong Kong in the 1950s and 1960s as it was becoming a major metropolitan centre. Ho would use the same Rolleiflex K4A throughout his career.

Upon seeing Ho's work for the first time in 2006, gallery owner Laurence Miller commented that "they felt like direct descendants of the Bauhaus, yet they were made in Hong Kong. They were abstract and humanistic at the same time."