The embodiment of the invention discloses a processing method for network communication function abnormity and a modem. The method comprises: when a modem in a mobile terminal is abnormal, the modem detects whether a common module in the modem is abnormal; if the common module of the modem is normal, the modem turns off a first protocol stack that is being used by the modem currently and a second protocol stack except the first protocol stack among a plurality of protocol stacks supported by the modem is selected; the modem starts the second protocol stack and network registration is carried out again by using the second protocol stack; and when the network registration is done successfully, the modem records current location information of the mobile terminal. Therefore, according to the embodiment of the invention, when the modem is abnormal, the modem can be recovered to be normal rapidly by switching other protocol stack to carry out network registration, so that a network communication function abnormity problem can be solved rapidly.