Born Dorothy Smith in Baywood, Louisiana, she grew up on the farm of her grandparents loving animals and nature, climbing trees, swinging on vines and playing football and softball. She was a cheerleader as a teenager and won some beauty contests. She was awarded the titles "Miss Baton Rouge" and, in 1957, "Miss New Orleans".

She went to New York to pursue a career in entertainment and started out as a model for toothpaste ads. She was featured as the "Letters Girl" on The Perry Como Show in 1957, and as the "Billboard Girl" on The Steve Allen Show in 1959. These and other TV appearances led New York photographers and newspaper reporters to award her the "Miss By-line" crown, which she wore on The Ed Sullivan Show.

Producer Hal Wallis saw the Sullivan episode and cast her in the role of Marjorie Burke in the movie drama Career (1959) starring Anthony Franciosa, Dean Martin and Shirley MacLaine. This was followed by a bit part in the musical comedy Li'l Abner (1959) and the role of a secretary in the comedy/romance Lover Come Back (1961) starring Rock Hudson, Doris Day and Tony Randall.

Douglas made numerous TV appearances, which include a famous episode of The Twilight Zone titled The Eye of the Beholder (1960), arguably the most famous episode of that legendary program. She also appeared on Ozzie and Harriet, Bachelor Father, and Thriller among other television series.

She had two husbands, Roland Bourgeois (married 1949-divorced 1954) and director Robert M. Leeds (married late 1970s-divorced). She and Bourgeois had one child, a son.

The turning point in Douglas' career came when she was chosen over 500 other actresses to play the role of Elly May Clampett on The Beverly Hillbillies. She starred on the program for all nine seasons, along with Buddy Ebsen, Irene Ryan, Nancy Kulp and Max Baer Jr. The Beverly Hillbillies became one of the longest-running series in television history and was the number one show in America its first two years.

Her final movie role was as Frankie in Frederick de Cordova's musical comedy Frankie and Johnny (1966) opposite Elvis Presley.

Douglas remained with The Beverly Hillbillies for the entire run of the series. In 1981, she returned for a made-for-TV reunion movie. Having no resentment about being so closely identified with one character, she still makes occasional public appearances in her hillbilly costume of blue jeans with trademark rope belt and a ruffled, pink blouse.

Donna Douglas became one of the most popular TV stars of the 1960's and one of the first blonde sex symbols to become a television icon, paving the way for Barbara Eden, Farrah Fawcett, Heather Locklear, and Pamela Anderson. Unusually modest for a Hollywood sex symbol, Douglas' post Hillbillies career was rather lackluster in part because she refused to act in projects in which her character would be put in sexual situations. Among the projects she declined was a stint on the daytime soap Santa Barbara.

She received her real estate license after The Beverly Hillbillies went off the air in order to have something to fall back on. She did not work in that field long, however, as she remained in show business and found other projects.

A devoted Christian, Douglas frequently performs gospel singer and speaks at churches across America. She recorded a gospel album in 1982 and later a country and gospel album two-record set in 1989. (A British pop singer in the 1960's also named Donna Douglas recorded a number of recordings including a U.K. hit "Message in a Bottle" and occasionally her discs are mistaken for the Hillbillies star.) She has also written a children's book titled Donna's Critters & Kids: Children's Stories with a Bible Touch, which has Bible stories featuring animals and is combined with a coloring book for ages two to seven.

She has remained busy making appearances, speaking for church groups, youth groups, schools and colleges. One key focus of her charitable work has been to appear and speak in support of various Christian childrens homes, mostly in her native south. She has also appeared at conventions and trade shows.

Donna Douglas lives in Huntington Beach, California, but still considers Baton Rouge, Louisiana, her hometown.