Embodiments of the present invention provide a charging information processing method and a gateway device. The method includes sending, to a gateway forwarding plane, a charging information identification set used for identifying charging information, saving first charging information sent by the gateway forwarding plane, where the first charging information carries a first charging information identification, which is an element in the charging information identification set, receiving second charging information sent by the gateway forwarding plane and saved by the gateway forwarding plane, where the second charging information carries a second charging information identification, which is an element in the charging information identification set, and combining the first charging information and the second charging information according to the first charging information identification and the second charging information identification. In this way, a disaster recovery capability can be effectively improved and charging reliability can be ensured.