Common household fruit flies of the species typically found in kitchens and around ripening fruits do not bite. These insects, sometimes called vinegar flies, are attracted to fruit because of the vinegar released as a byproduct during the natural fermentation process.
Because fruit flies do not feed on blood like some other species of insects, they do not have the ability to bite. Other types of flies are commonly mistaken for fruit flies, however. Standard house flies and stable flies do bite, as do a particular type of fly called biting midges that are often found outside in damp areas.