Born in Shanghai, Yao began performing with a radio appearance there in 1935 at the age of 13. She was signed to .
Following the seizure of power in China in 1949, popular music was considered ideologically suspect and Yao fled to Hong Kong in 1950 to continue her singing career there. She stopped singing in 1967 with the death of her brother, but took an executive position with in 1969. In 1970, she returned to performing and traveled to Taiwan to perform there for the first time and sought unsuccessfully to sign Teresa Teng to EMI for the Hong Kong market. She retired officially in 1975 but remained supportive of singers such as Wakin Chau.
During the 1930s and 40s, Yao Lee's high, soft singing style was typical of Chinese popular music of the time. She performed numerous popular standards, such as ''Wishing You Happiness and Prosperity'' with her brother Yao Min. She is famous for her 1940 version of ''Rose, Rose, I Love You'', later recorded by Frankie Laine in the United States with English lyrics. . Yao was known as "the Silver Voice" alluding to fellow Shanghai singer Zhou Xuan who was known as "the Golden Voice".
With increasing Western influence in the region after World War II and her move to Hong Kong, Yao Lee's singing changed. She was introduced to more Western popular music and became an admirer of singer Patti Page whom she emulated by lowering her voice and incorporating some vocal mannerisms. As a result, Yao is sometimes called "Hong Kong's Patti Page."
Yao was extremely prolific with over 400 gramophone records attributed to her.