A call processing method and apparatus in a private wireless communication system or WPBX, by which when the WPBX service subscriber originates a PLMN voice call in the private wireless communication service zone without inputting the preset identification number, the call is forwarded to the PSTN and/or wired/wireless Internet linked to the WPBX instead of being sent to the PLMN so that the WPBX service subscriber can be provided with a more convenient communication service at a cheaper price when he/she wants to be provided with the PLMN service.