Martinez was born in Trinidad, Colorado. Her mother brought the family to the Bay Area during WWII and found work as an electrician in one of the shipyards.
Martinez is a graduate of UC Berkeley, and the first in her family to attend college. She also received a Masters in Social Work from UC Berkeley in 1966.
In 1977, Martinez was appointed Assistant Secretary for the Office of Human Development Services, U.S. Department of Health, Education and Welfare by President Jimmy Carter, the first Latina appointed to a sub-cabinet level position in the history of the nation. 1