Wanting a career in films, Mara Corday came to Hollywood while still in her teens and found work as a showgirl at the Earl Carroll Theatre on Sunset Boulevard. Her physical beauty brought jobs as a photographer's model that led to a bit part as a showgirl in the 1951 film Two Tickets to Broadway. She signed on as a Universal International Pictures (UI) contract player where she met actor Clint Eastwood with whom she would remain lifelong friends. With UI, Corday was given small roles in various B-movies and television series. In 1954 on the set of Playgirl she met actor Richard Long. Following the death of Long's wife, the two began dating and married in 1957.

Her roles were small until 1955 when she was cast opposite John Agar in the Sci-Fi B-movie that proved a success. She had more co-starring roles in such genres as well as in a number of Western films. Respected film critic Leonard Maltin said that Mara Corday had "more acting ability than she was permitted to exhibit."

Mara Corday appeared as a pinup girl in numerous men's magazines during the 1950s and was the Playmate of the October 1958 issue of Playboy. In 1956, she had a recurring role in the ABC television series Combat!. From 1959 to early 1961, Corday worked exclusively doing guest spots on various television series. She then gave up her career to devote her time to raising a family. During her seventeen-year marriage to Richard Long she would have three children.

A few years after her husband's passing in 1974, Corday's friend Clint Eastwood offered her a chance to return to filmmaking with a role in his 1977 film The Gauntlet. She would act with him again in Sudden Impact (1983), Pink Cadillac (1989), and in her last film, 1990's The Rookie.