The present invention relates to a method and device for controlling charging in a mobile communication system. The method for controlling charging in a mobile communication system is characterized by comprising the steps of: generating, by a service provider, a sponsor coupon to transmit to a terminal when a sponsor service request transmitted from the terminal is received; receiving, by the terminal, the sponsor coupon to transmit to an operator; setting, by the operator, a filtering and charging rule for sponsor traffic by using the sponsor coupon, and notifying the terminal; requesting, by the terminal, the sponsor service to the service provider again, and receiving a sponsor traffic service from the service provider; and charging, by the operator, the service provider for the sponsor traffic.