Percy Francis Westerman (1876 – 22 February 1959) was a prolific author of children's literature, many of his books adventures with military and naval themes.
He was born in Portsmouth, England in 1876, and educated at Portsmouth Grammar School, before taking up a clerical appointment at Portsmouth Dockyard at the age of twenty. He married Florence Wager, of Portsmouth, in 1900. Always keen sailors, they spent part of their honeymoon sailing in the Solent. Their son, John F.C. Westerman, born in 1901, also wrote adventure books for boys.