She was born Gloria Pina Ramos Luna in Mexico City the 19th of April 1919. Her father was Pedro Méndez Armendáriz (1884-1954), and her mother, María Ramos Luna (1887-1960). Gloria took her stage name from her mother, who was known as Laura Marín; this was the surname she used for her acting career. Her parents were not married at the time of her birth, but even if her father did give her his last name, Gloria decided to keep her mother's last name because she grew up with her and wanted to honor her. She had two brothers (Álvaro and Guillermo) and a sister (María Luisa "Lili Marín"). She was lived most of her life in Mexico City.

Her first performance was at the age of five in a "carpa" tent, where her mother used to play the piano after the hard times of the Mexican Revolution. The main singer did not show up so Gloria jumped up to the stage and asked the musical director to play "La Mocosita", an Argentine tango. She was missing a tooth so the audience went crazy when they listened to the little girl singing and hissing; they loved her. Her first stage name was "La pequeña Glorina" (or The little Glorina) and performed in small theaters all over the Mexican Republic with great actors, such as Cantinflas.

Marín began her film career with Cantinflas, Carlos López "Chaflán" and some others, playing small roles until 1941. She had her first big success in ¡Ay Jalisco... no te rajes! (1941), where she met her true love Jorge Negrete, with whom she lived from 1942 to 1952. For her role in Si Adelita se fuera con otro (1948), she was nominated for the 1949 Ariel Award for Best Actress. One of the most famous and beautiful actresses in Mexico, she performed for almost sixty years and filmed over 100 motion pictures. Married to Jorge Negrete and later to Abel Salazar, Marín had one daughter, Gloria Virginia Guadalupe Ramos Luna.

She died on the 13th of April of 1983 at Hospital Español in Mexico City at the age of 63.