Amoruso founded Nasty Gal, a women's fashion retailer, which went on to be named one of "the fastest growing companies" by Inc. Magazine in 2012.

[4] In 2017, Amoruso founded Girlboss Media,[5][6] a company that creates content for women in the millennial generation to progress as people in their personal and professional life.

[8] After being diagnosed with depression and attention deficit hyperactivity disorder (ADHD) in her adolescence, she dropped out of school and began homeschooling to help cope with these issues.

As a young adult, Amoruso lived a nomadic lifestyle, hitchhiking on the West Coast, dumpster diving, and stealing.

To get the health insurance for surgery, she worked in the Academy of Art University lobby checking student IDs.

[11][13] At age 22 while working as a security guard at San Francisco's Academy of Art University,[14] Amoruso opened an online eBay store, which she called Nasty Gal Vintage, named after the 1975 album by funk singer and style icon Betty Davis.

She has previously stated that she left voluntarily because of the rules preventing sellers from leaving negative feedback for customers.

[29] On January 12, 2015, Amoruso announced she was stepping down as CEO of Nasty Gal, knowing the company could not continue under the current leadership.

[30] In November 2016, the company was reported to be filing for Chapter 11 bankruptcy protection, with Amoruso resigning as executive chairwoman.