Diana Roselyn Trask (born 23 June 1940) is an Australian-American singer, songwriter and author. She was considered to be one of the first Australian music artists to find success in the United States, particularly in the genres of pop and country.

Born in Camberwell, Victoria, Trask had a musical upbringing and left school in her teens to pursue music full-time. She began her career in Melbourne and Sydney during the late fifties, appearing on local television and singing at clubs. After serving as Frank Sinatra's Australian opening act, she left for the US in 1958. She settled in New York City and received a recording contract from Mitch Miller of Columbia Records in 1960. Trask then became a series regular on his television program, Sing Along with Mitch and recorded two studio albums released by Columbia 1961: Diana Trask and Diana Trask on TV. Trask then married American businessman, Thom Ewen, who became her full-time manager. The couple moved back to Australia here her television program, The Di Trask Show, was syndicated for one season in 1965.

Trask then resettled in the US and reinvented herself as a country music artist. Settling in Nashville, Tennessee, Trask was signed to Dot Records in 1968 where her cover of "Hold What You've Got" made the US country chart. It was included on her first country album, Miss Country Soul, which also made the US country chart. Trask's music continued making the US country charts and she toured alongside performer Roy Clark in several Las Vegas engagements. She reached her peak commercial success in the middle seventies with four top 20 country songs: "Say When", "It's a Man's World", "When I Get My Hands on You" and "Lean It All on Me". Her 1974 single, "Oh Boy", was a top ten song in Australia. She remained popular in Australia through the 1980s with albums like the gold-ceritifed One Day at a Time (1981).

Trask went into semi-retirement as the eighties decade progressed. Sporadically, she returned to her music career including performing at the 1985 Australian Grand Final. For the most part, Trask and her husband sailed the Caribbean, along with operating a store in Alaska. She also returned to college and received a degree in herbal medicine. In 2009, Trask's husband died and she returned to her career. She co-wrote a memoir in 2010 called Whatever Happened to Diana Trask and released three albums on her own label titled Trask Enterprises: Country Lovin' (2010), Daughter of Australia (2014) and Memories Are Made of This (2016).

Trask was born in Camberwell, a suburb of Melbourne, Victoria. She was one of three children born to Lew and Thelma Trask. Her older sister, Patsy Anna, died at the age of two after contracting Pink's Disease. She also has an older brother, Peter. Her father was the owner of a furniture business while her mother was a music teacher. Her cousin was Opera singer Dame Nellie Melba. She attended a local state school but transferred to a Catholic school because her mother found her challenging to manage. Spending week nights at the Catholic school, Trask only returned to her family's home on weekends. At age 11, her family sent her to another Catholic school with better resources in Melbourne. She enjoyed singing from an early age and routinely asked her mother to give her vocal lessons. However, her mother wanted her to wait until she was a teenager when her voice fully developed. Yet in August 1949 she won singing competition and then briefly received formal vocal lessons from her mother.

Trask dated her first boyfriend at age 15, but broke up with him shortly after discovering him kissing her mother in the family home. Her relationship with her mother then became strained. "In my confusion and self-doubt I thought she had betrayed me too and I held a grudge against her for a long, long time," she wrote in her memoir. Trask ultimately dropped out of school around age 16 and worked several minimum wage jobs while also working towards becoming a professional singer. She started received vocal lessons from Melbourne instructor Jack White, who helped her audition for the local Channel Seven television competition called Swallow's Parade. Trask won the competition and then won a second talent show, TV Quest, in 1957. Her first pair of singles were released in 1958 and 1959: "Going Steady" (issued by W&G) and "Soldier Won't You Marry Me" (issued by Roulette). She then did a small tour in Southern Australia and returned to Melbourne occasionally performing on the local television network. She often performed on a program called In Melbourne Tonight (IMT) but ended after it was rumored that Trask's father would sponsor the show through his furniture business. He ultimately declined which resulted in Trask losing her singing position.

Trask decided to move to Sydney where she was told she would find steadier singing opportunities. In Sydney, she lived with a friend of her father's and then with a group of girls in a small home located behind a doctor's office. Trask found work performing with the Australian Jazz Quartet and at the Sky Lounge in Sydney. She then obtained her own radio program on the ABC network called Diana Trask Sings, which was heard by American promoter Lee Gordon. Gordon arranged for her to open for international music artists, beginning with Frank Sinatra in 1959. Trask then opened shows for Sinatra in Melbourne and Sydney. Gordon then arranged for her to open shows for Sammy Davis Jr. in Melbourne, Sydney and Brisbane. Both performers encouraged Trask to move to the United States and in 1959 she officially left for the country. She stayed at Sinatra's Los Angeles home for several days. He offered Trask assistance with her career, but she declined insisting she could do it herself. She then moved to New York City.

Upon her New York arrival, Trask met agent Roz Ross (an associate of Lee Gordon's) who agreed to take her on. She debuted as a jazz singer at The Blue Angel nightclub in August 1959. Ross then arranged for Trask to tour throughout the United States, notably in Houston, Texas. She also appeared on the television program, Don McNeill's Breakfast Club. Ross then organized Trask to record a demo record for Columbia Records producer Mitch Miller. The pair then met with Miller in New York and he ultimately signed Trask to a contract with Columbia in 1960. Miller then brought Trask to New York's Tin Pan Alley neighborhood to record several selections. Trask recalled Miller reprimanding her when her vocal style "got too swingy" and on occasion telling her to leave the session until "you feel like doing it my way". Among her early Columbia singles was the 1961 pop ballad "Long Ago Last Summer", which Billboard called "highly spinnable". The song reached number 26 on Australia's pop chart. Two more 1960 Columbia singles were reissued by Coronet Records in Australia and made the top 60 of their pop chart: "A Guy Is a Guy" and "Our Language of Love".