Ontiveros died Thursday at a hospital in Whittier, Calif., a suburb southeast of Los Angeles, after a brief battle with liver cancer, according to longtime friend and family spokesman Jerry Velasco.
She was perhaps best known for her role in "Selena," the 1997 biopic based on the life story of the Tejano pop star. Ontiveros played Yolanda Saldivar, who in real-life was convicted of killing Selena Quintanilla. The film launched the career of Jennifer Lopez, who played the title part.
Lopez said Friday she was "tremendously saddened by the news of Lupe's passing!"
"I've enjoyed her work throughout the years," Lopez said in a statement. "She was a great actress and working with her in 'Selena' was an unforgettable experience. She will truly be missed."
Ontiveros worked steadily in TV and film for more than 35 years.
"I want to go from the set to the grave," she quipped in 2010 while receiving a lifetime achievement award from the National Association of Latino Independent Producers. "From the stage to the grave, that's how I want go."
Her credits include "Real Women Have Curves," TV's "Desperate Housewives" and as in "The Goonies" many, many turns as a housekeeper. She once estimated she played a maid more than 300 times on the stage and screen.
"I've had a hell of a good time playing those maids," she told LA Weekly in 2002. "Each one to me is very special ... No matter how much I resent the stupidity that is written into them, the audacity that the industry has when they portray us in such a nonsensical, idiotic, such oh my God! such a degrading manner, still, my humor survives in these maids. I'm very proud of them."
Born Guadalupe Moreno in El Paso, Texas, on Sept. 17, 1942, Ontiveros caught the acting bug in 1972 when she answered a newspaper ad for movie extras. She went on to help establish the Latino Theater Company in Los Angeles and advocated for Latino performers throughout her career.
"She worked tirelessly to perfect her craft and open doors for countless Latinos along the way," said Alex Nogales, president of the National Hispanic Media Coalition. "Hollywood never gave her the lead role, but in our hearts she will be remembered as our leading lady. She will be deeply missed by all of us."
U.S. Secretary of Labor Hilda L. Solis cited the actress as an inspiration.
"Lupe Ontiveros' great talent extended far past television, stage and motion pictures," Solis said in a statement. "Indeed, she was a fine actress, but more than that, she was a woman of great action. And she was my friend for more than 20 years."
Ontiveros is survived by her husband, three sons and two granddaughters.