Irwin M. Marcus (March 18, 1919 – October 3, 2021) was an American board certified psychiatrist, neurologist, psychoanalyst, medical educator, visual artist, and sculptor. He was a practicing psychiatrist, sex therapist, marriage counselor, psychoanalyst, child psychiatrist, and family counselor for over six decades. Marcus started the Child Psychiatry Program at Tulane University School of Medicine in 1952, he was a Founder and President of the New Orleans Psychoanalytic Institute, Emeritus Professor of Clinical Psychiatry at LSU School of Medicine, and was considered a psychoanalytic scholar.