Provided is a tagless mobile ticket service method, which enables a user possessing a wireless terminal, in which a payment application capable of paving bills is installed, to pay for usage fees without being tagged at a ticket gate machine, The tagless mobile ticket service method includes: a user entry detecting step in which a ticket gate machine senses that a user possessing a user terminal accesses a ticket gate; a user information processing step in which bill payment information is acquired from the user terminal; a validity confirmation step in which the validity of the bill payment information is determined; and a user fee processing step in which a door is opened and a bill is paid using the bill payment information, if it is determined that the bill payment information is valid.