The Arizona Court of Appeals ruled Friday that Cindy Vong can sue over the Arizona Board of Cosmetology's threat to pull her license if she didn't stop offering the pedicure, which uses fish to eat dead skin off clients' feet.
The board alleged the fish were unsafe because they couldn't be sterilized.
Conservative watchdog group The Goldwater Institute had filed a civil suit on her behalf, saying the broad violated Vong's right to run her business in the Phoenix suburb of Gilbert.
The lawsuit says the board lacks jurisdiction because the pedicure isn't a cosmetic service.
A lower court had dismissed the suit.