Yma Sumac may have been born on September 10, 1922 in Ichocán, Cajamarca, Peru as Zoila Augusta Emperatriz Chavarri del Castillo. Other dates mentioned in her various biographies range from 1921 to 1929. Some sources claim that she was not born in Ichocá, but in a nearby village or possibly in Lima, and that her family owned a ranch in Ichocá where she spent most of her early life. It is also claimed that she is an Incan princess directly descended from Atahualpa. The story that she was actually born Amy Camus (Yma Sumac read backwards) in Brooklyn or Canada is a hoax. It is documented in this reference that she was known as Imma Sumack in recordings made before she went tot the U.S.; Capitol Records changed the spelling to the more exotic "Yma Sumac".

She first appeared on radio in 1942, and married composer and bandleader Moisés Vivanco on June 6 the same year. Using the stage name Imma Sumack , she recorded at least eighteen tracks of Peruvian folk songs in Argentina in 1943. These early recordings for the Odeon label featured Moisés Vivanco's group, Compañía Peruana de Arte - a group of 46 Indian dancers singers and musicians. In 1946, Yma Sumac and Vivanco moved to New York City, where she performed with the Inca Taky Trio, with Moisés Vivanco on guitar, Yma Sumac's cousin Cholita Rivero singing contralto and dancing, and Yma Sumac providing the soprano, until being signed by Capitol Records in 1950.

During the 1950s, she produced a series of legendary lounge recordings featuring Hollywood-style versions of Incan and South American folk songs, working with the likes of Les Baxter and Billy May. The combination of her extraordinary voice, exotic looks and stage personality made her a hit with American audiences. During the height of her popularity, she appeared in the films Secret of the Incas (1954) and Omar Khayyam (1957); she became a U.S. citizen July 22, 1955.

In 1957, she and Vivanco divorced. In 1959 she gave her voice for the song "I Wonder" from the Sleeping Beauty film. They remarried that same year before divorcing again in 1965. They had one son, Charles, born in 1949. Apparently due to financial difficulties, Yma Sumac and the original Inca Taky Trio went on a world tour in 1961, which lasted for five years. They performed in 40 cities in the Soviet Union, and afterwards all over Europe, Asia and Latin America. Their performance in Bucharest, Romania was recorded as the album Recital, her only 'live in concert' record. Yma Sumac spent the rest of the 1960s performing sporadically.

In 1971, she released a rock album, called Miracles, and then returned to live in Peru. She performed in concert from time to time during the 1970s in Peru and later in New York. In the 1980s, she had a number of concerts both in the U.S. and abroad including at New York's The Ballroom in 1987 and several San Francisco shows at the Theatre on the Square among others. In 1987, she also recorded a song for Stay Awake, an album of songs from Disney movies, produced by Hal Willner.

In 1989, she sang once again at The Ballroom in New York. In March 1990, she played the role of Heidi in Stephen Sondheim's Follies, in Long Beach, California - her first attempt at 'serious theater' since Flahooley in 1951. She also did several concerts in the summer of 1996 in San Francisco and Hollywood and two more in Montreal, Canada in July 1997 as part of the Montreal International Jazz Festival. She currently lives in Los Angeles.

In 1992, Gunther Czernetsky directed a documentary titled Yma Sumac - Hollywoods Inkaprinzessin (Yma Sumac - Hollywood's Inca princess).

On May 2, 2006, Sumac flew to Lima, where she was given the "Orden del Sol" award by Peruvian President Alejandro Toledo, and the Jorge Basadre medal by the Universidad Nacional Mayor de San Marcos.