Parker broke into theatre after service in the Navy and by 1951 was in the national company of "Mr. Roberts" which brought him to Hollywood. He was immediately cast in films with a Western or pioneer theme. His first effort, "Untamed Frontier" (1952), was about a range war in Texas, but Parker did not click in movies. Instead, he could be seen as a potential beau for "My Little Margie" in several episodes of that sitcom in the early 50s. In 1954, Walt Disney hired Parker to play Davy Crockett in an episode of a new series his studio was doing for ABC as part of a deal through which ABC funded 35 percent of Disneyland. Originally planned as three episodes, with Crockett dying at the Alamo in the last one, the viewer response was so great that Disney had to produce three more "prequel" installments of the tales of the Tennessee frontiersman and congressman. Although many might swear to this day that "Davy Crockett" was an ongoing series, it never was. (Two installments were also released as features.) Yet throughout America, boys wore coonskin caps and fringed cowhide jackets in homage to their hero. Parker, who was also a singer, did not get to record the famed "Davy Crockett" theme song (Bill Hayes had that success) but he did learn about the business of merchandising.
In 1956, Parker made a feature for Disney about Doc Grayson, the leader of a wagon train, called "Westward Ho the Wagons" which served as the basis for the "Doc Grayson" installments of the Disney show. In 1958, Parker made what is perhaps his most famous feature, Disney's "Old Yeller", with youth star Tommy Kirk as his son. The film was Disney's first live action success and played as a classic family tale for so many years it is still fodder for stand-up comedy quips in the 90s. Parker changed his image a bit singing on "The Ed Sullivan Show" and on an Ethel Merman special in 1959, and he tried a new switch playing the junior senator role done on the big screen by James Stewart in the TV version of "Mr. Smith Goes to Washington" (ABC, 1962-63). Like Stewart, Parker oozed earnestness, but the sitcom lasted only one season. Parker was back in buckskin for his next outing, as the Kentucky pioneer "Daniel Boone" (NBC, 1964-70). This time Parker also recorded the theme song to the show, although cast member Ed Ames had more of a reputation as a singer. Following the 1972 NBC TV-movie "Climb an Angry Mountain", in which he was a widowed sheriff and a busted pilot for a comedy series "The Fess Parker Show" (1974), Parker retired from show business to concentrate on his businesses and extensive real estate holdings, much of it in the Santa Barbara area.