Palakkalthazhe Mathai Mathew (January 1933 – 28 September 2020) popularly known as Dr. P. M. Mathew Vellore, was an Indian psychologist, columnist, writer and actor from Kerala, credited with popularizing the subjects of Psychology and Sexology in Kerala. He was known for his clinical service as well as for the several psychology-related articles and columns he wrote in Malayalam periodicals during the last quarter of 20th century. He was also the author of over 20 books and acted in three Malayalam films.