The mobility model of nodes plays an important role in affecting the quality of the tactical subnet. The unique characteristics of the tactical subnet may weaken the significance of research on the common mobility model. In this paper, firstly, we make a careful analysis and a simulation of the Random Waypoint Mobility Model (RWP) and the Reference Point Group Mobility Model (RPGM). Subsequently, according to the characteristics of the tactical task and the fact that the mobile nodes do not always move blindly along a random or fixed path, we propose a new group mobility model named Probabilistic Reference Point Group Mobility Model (p-RPGM). Finally, taking a tactical team as an example, the above three mobility models are simulated and compared based on OPNET simulation software, to reveal the influence of different mobile behaviors of nodes on network performance.