Julia Prinsep Stephen (née Jackson; formerly Duckworth; 7 February 1846 – 5 May 1895) was an English Pre-Raphaelite model and philanthropist. She was the wife of the biographer Leslie Stephen and mother of Virginia Woolf and Vanessa Bell, members of the Bloomsbury Group.
Julia Prinsep Jackson was born in Calcutta to an Anglo-Indian family, and when she was two her mother and her two sisters moved back to England. She became the favourite model of her aunt, the celebrated photographer Julia Margaret Cameron, who made more than 50 portraits of her. Through another maternal aunt, she became a frequent visitor at Little Holland House, then home to an important literary and artistic circle, and came to the attention of a number of Pre-Raphaelite painters who portrayed her in their work.