Spelling was born Carole Gene Marer in Beverly Hills, California, the daughter of Augusta Gene (née Rosen) and Merritt Marer. In 1963 Candy graduated from Beverly Hills High School. In 1968, Candy Spelling (Carole Gene Marer) married producer/writer Aaron Spelling. Together they had two children, Victoria Davey Spelling and Randall Gene Spelling, both of whom became actors as teenagers, as Tori Spelling and Randy Spelling. They appeared in several of Aaron’s productions, most notably in Beverly Hills, 90210.

She currently owns a home called Spelling Manor. According to her lawyer, she paid $47 million for a two-story condo atop a Century City residential tower that is still under construction in July 2008. Her lawyer said Spelling was moving in order to downscale her living space after her husband's death in 2006. In March 2009, Candy put her Holmby Hills mansion up for sale. The property is , , with an estimated 100 rooms and is said to be the largest home in Los Angeles County. The asking price is $150 million, the most expensive residential listing in the U.S. at the time.

She is currently a member of the Los Angeles Coliseum Commission, a Commissioner for the Department of Recreation and Parks (for the City of Los Angeles), and a member of the board of L.A.’s Best, the Mayor's group that provides reading programs to schools in L.A. She is a regular columnist for The Huffington Post, Los Angeles Confidential magazine, and TMZ.com (Spelling It Out). Her autobiography, Stories from Candyland, was released in March 2009. The book hit the NY TIMES bestseller list two weeks after publication. It was also the #1 book at L.A.'s Book Soup.

Candy has two grandchildren through Tori, Liam Aaron McDermott (born March 13, 2007) and Stella Doreen McDermott (born June 9, 2008). She and Tori had been estranged for years. On April 13, 2009, Candy wrote an open letter on her website to Tori expressing her interest in having a better relationship with her, as well as spending more time with her grandchildren. She wrote that the main reason for her letter was that she knew Tori visits her site regularly, and Candy wasn't able to reach Tori via telephone, email, or text message.

Candy and her daughter Tori have reconciled as of 2010.