Ann M. Martin was born and raised in Princeton, New Jersey. She graduated from Smith College in 1978 with a double major in psychology and elementary education. Ann started her career as a teacher and then became an editor of children's books. Her first published book was Bummer Summer in 1983. However, she is best known for her Baby-sitters Club series of children's books.

In 1990, Ann founded the Ann M. Martin Foundation, which provides grants to causes benefiting children, education and literacy programs, and homeless people and animals. She currently resides in Hudson Valley, New York.