A single cell point to multi-points (SC-PTM) network system and a data transmission method thereof are provided. The SC-PTM network system includes a base station and a first mobile station group and a second mobile station group. The base station multicasts a message to the mobile station groups via a first bearer, and receives a plurality of confirmation notifications from the mobile station groups. The base station determines a data transmitting status of the mobile stations and re-transmits the message to the mobile stations of the group which has higher priority.
