Peter Monamy painted storms, calms, Thames views and naval actions, working on canvas, panel and copper. He also etched and engraved.

In 1736 Monamy, together with William Hogarth and Francis Hayman, were commissioned to assist in the decorations of the newly-opened pleasure gardens at Vauxhall. Taking up a tradition which he had inherited from Dutch painters, Monamy nurtured an English school of marine painting. Monamy's daughter married the marine painter Francis Swaine and his grandson was another marine artist, Monamy Swaine.