A method for charging a proximity based service in a user equipment of an LTE-based wireless communication network, wherein the proximity based service is wireless communication performed through radio signals directly between user equipments proximate to each other, comprising: - determining whether it is required to obtain charging related information of the proximity based service used by the user equipment based on any one of the following: o a network connection state and/or access type from the user equipment to the wireless communication network or through a predetermined condition; o a service type and/or application type of the proximity based service; o control information from the wireless communication network; - obtaining (S21) charging related information of the proximity based service used by the user equipment based on a result of the determining; - generating (S22) a charging request for the proximity based service used by the user equipment based on the charging related information, wherein the generating (S22) comprises: o determining a charging mode for the proximity based service; and o generating (S22) a charging request for the proximity based service used by the user equipment based on the charging related information and the charging mode; and - transmitting (S23) the charging request to a charging system of the wireless communication network, wherein the transmitting (S23) comprises: ∘ transmitting (S23) the charging request to an offline charging system or online charging system of the wireless communication network according to the determined charging mode. - determining whether it is required to obtain charging related information of the proximity based service used by the user equipment based on any one of the following: o a network connection state and/or access type from the user equipment to the wireless communication network or through a predetermined condition; o a service type and/or application type of the proximity based service; o control information from the wireless communication network; o a network connection state and/or access type from the user equipment to the wireless communication network or through a predetermined condition; o a service type and/or application type of the proximity based service; o control information from the wireless communication network; - obtaining (S21) charging related information of the proximity based service used by the user equipment based on a result of the determining; - generating (S22) a charging request for the proximity based service used by the user equipment based on the charging related information, wherein the generating (S22) comprises: o determining a charging mode for the proximity based service; and o generating (S22) a charging request for the proximity based service used by the user equipment based on the charging related information and the charging mode; and o determining a charging mode for the proximity based service; and o generating (S22) a charging request for the proximity based service used by the user equipment based on the charging related information and the charging mode; and - transmitting (S23) the charging request to a charging system of the wireless communication network, wherein the transmitting (S23) comprises: ∘ transmitting (S23) the charging request to an offline charging system or online charging system of the wireless communication network according to the determined charging mode. ∘ transmitting (S23) the charging request to an offline charging system or online charging system of the wireless communication network according to the determined charging mode. <EOS>