A native of Licenza and the daughter of Ercole Costantini and Geltrude Montori, Lattanzi began her acting career in 1922 when she met Vittorio De Sica, who in turn, introduced her to Tatyana Pavlova, who coached her into acting. Lattanzi was mainly active on stage during the 1920s before making her screen debut in 1930 and she was well known for her portrayals of women of noble birth. In 1954, Lattanzi began focusing her attention on television
Because of her drawl, persuasive voice, she also turned to the Cooperativa Doppiatori Cinematografici during the 1940s.