A method, in an interworking function device, of distributing a group message of machine type communication, the method comprising the steps of: a. receiving the group message from a service capability server, wherein the group message includes location/area information, radio access technology information, external group identifier information and/or application layer data; b. selecting a transmission mode under a predetermined policy according to the group message or obtaining the transmission mode by querying a home location register or a home subscriber server according to the group message; c. translating the location/area information into a geographical area in which the group message is transmitted and updating the group message with the geographical area; d. mapping the external group identifier information to an internal group identifier according to information in the home location register or the home subscriber server and updating the group message with the internal group identifier information to obtain an updated group message; e. querying the home location register or the home subscriber server according to the updated group message about a core network node or a broadcast system node for transmitting the group message; f. connecting the interworking function device with a cell broadcast center or a broadcast multicast service center to support transmission of the group message in a broadcast mode; and g. transmitting the updated group message to the core network node or the broadcast system node in the selected transmission mode; characterized in that: the predetermined policy in the step b includes: that if the group message includes pure service data, then the transmission mode is a cell broadcast service mode or a multimedia broadcast multicast service mode, and transmitting the updated group message in the step g comprises transmitting the pure service data to the broadcast system node; wherein an indicator indicating that the transmitted contents are pure service data is carried by a transmitted application layer and wherein the pure service data are transmitted in push mode. a. receiving the group message from a service capability server, wherein the group message includes location/area information, radio access technology information, external group identifier information and/or application layer data; b. selecting a transmission mode under a predetermined policy according to the group message or obtaining the transmission mode by querying a home location register or a home subscriber server according to the group message; c. translating the location/area information into a geographical area in which the group message is transmitted and updating the group message with the geographical area; d. mapping the external group identifier information to an internal group identifier according to information in the home location register or the home subscriber server and updating the group message with the internal group identifier information to obtain an updated group message; e. querying the home location register or the home subscriber server according to the updated group message about a core network node or a broadcast system node for transmitting the group message; f. connecting the interworking function device with a cell broadcast center or a broadcast multicast service center to support transmission of the group message in a broadcast mode; and g. transmitting the updated group message to the core network node or the broadcast system node in the selected transmission mode; the predetermined policy in the step b includes: that if the group message includes pure service data, then the transmission mode is a cell broadcast service mode or a multimedia broadcast multicast service mode, and transmitting the updated group message in the step g comprises transmitting the pure service data to the broadcast system node; wherein an indicator indicating that the transmitted contents are pure service data is carried by a transmitted application layer and wherein the pure service data are transmitted in push mode.