A method for construction a WVPN for a CDMA system is disclosed. The method includes a first step for registering a private network group and extension number to the SCP and judging whether a call by a certain calling subscriber corresponds to an extension number or a MDN (Mobile Directory Number) when a certain calling subscriber calls a certain receiving subscriber of the same group as the calling subscriber, and a second step for constructing a mobile communication network using the MDN in the case that as a result of the first step the call by the calling subscriber corresponds to the MDN and constructing a WVPN in the case that the call by the calling subscriber corresponds to the extension number, wherein the method for constructing a WVPN (Wireless Virtual Private Network) for a CDMA system includes a mobile telephone serviced by a private network group, a BTS (Base Transceiver System) for transmitting and receiving a message with the mobile telephone, a BSC (Base Station Controller) for managing the BTS, a MSC (Mobile Switching Center) including a MSA (Mobile Signaling Access), a MCC (Mobile Call Control), and a VLR (Visitor Location Register), a HLR (Home Location Register), and a SCP (Service Control Point) for storing an extension number with respect to a calling subscriber serviced by a private network group, for thereby constructing the WNPN using a certain extension number between subscribers for a WVPN group.