Born in Venice, Barbara was adopted and baptized into the Strozzi family. She was most likely illegitimate, daughter of Giulio Strozzi and Isabella Garzon, his long-time servant and heir. Giulio encouraged his daughter's talent, even creating an academy in which Barbara's performances could be validated and displayed publicly. He seemed to be interested in exhibiting her considerable vocal talents to a wider audience. However, her singing was not her only talent. She was also compositionally gifted, and her father arranged for her to study with composer Francesco Cavalli.

It is conceivable that Strozzi may have been a courtesan, however, she also may have merely been the target of jealous slander by her male contemporaries. She appears to have led a quiet, if not slightly unusual life; there is evidence that at least three of her four children were fathered by the same man, Giovanni Paolo Vidman. He may have been her husband or a paramour. After Vidman's death it is likely that Strozzi supported herself by means of her savvy investments and by her compositions. He did not, apparently, leave anything to her or her children in his will.

Strozzi died in Padua in 1677 aged 58. Strozzi is believed to have been buried at Eremitani When she died without leaving a will, her son Giulio Pietro claimed her inheritance.