Patricia Marjorie "Pat" Ralph (5 April 1920 – 23 March 1995) was a New Zealand marine biologist and university lecturer. She was born in Wellington, New Zealand in 1920. She graduated from Victoria University College with a Bachelor of Science in 1941 and a Master of Science two years later. She remained as a demonstrator at Victoria College and became a junior lecturer and then received a tenured position in 1949.