Her beauty and charisma drew the attention of film director Fernando de Fuentes, who gave her the female lead role of Crucita in the rural musical Allá en el rancho Grande (1936), opposite Tito Guizar.

Some critics consider the unexpected success of this film throughout Latin America as marking the start of the Golden Age of Mexican cinema.

However, although it was the only important female character, the adventure film focused on the male cast, headed by Alan Ladd and Brian Donlevy.

Fernández continued her career in Mexico, starring in films like Flor de durazno (1945), Ramona (1946), Cantaclaro (1947), Solo Veracruz es Bello (1948), Doña Perfecta (1950), playing the daughter of Dolores del Rio, and Los Hijos del Rancho Grande (1956).

In 1992, she returned to the cinema with the film Los Años de Greta, opposite Beatriz Aguirre and Meche Barba.