Pieter van Laer is mainly known for his genre scenes set in Italianate landscapes as well as for his landscapes and animal scenes. He also painted some battle scenes. He further engraved a number of plates of animals. He was one of the first artists to develop the painting of cattle as a specialist genre. He left one painting with a religious theme, the "Annunciation to the shepherds" (Museum Bredius, The Hague). This composition is also van Laer's earliest surviving cattle painting. His paintings were typically of a small format.