Florence Susan Harrison was an English Australian Art Nouveau and Pre-Raphaelite illustrator of poetry and children's books. Many of her books were published by Blackie and Son. She illustrated books by notable Pre-Raphaelite circle poets Christina Rossetti, William Morris and Sir Alfred Tennyson.

Florence Harrison was born in Brisbane, Australia, in 1877 to Lucy and Norwood Harrison. From 1922, she lived in the London area. Around 1940 she moved to Brighton, England, to live with her cousin Isobel. She remained there until her death in 1955.