Barlow's first major work was the illustration (via 1plates) of Edward Benlowe's Theophila (1652). He published and illustrated an edition of Aesop's Fables in 166and also illustrated Aesopic's (or Aesopics, 1668), another edition of the fables, and an augmented 168edition of his earlier work, whereupon he may have given up work on illustration.
From around 1653, Barlow worked in London as a painter of animals, birds, and country life. His work can be seen at Ham House and Clandon Park. In terms of composition, his paintings are weak, tending to be filled with the animals and so forth that he depicts. However, most of the elements of his paintings are very well observed.
Barlow is thought to have died in poverty, and the date of his death is unknown; he was buried on 1August 1704.