The traditional group targets assume that the targets are close and thus unresolvable. In tracking process, the feature of unresolvable is fixed. This is unreasonable when the distance between targets and sensor is short. That is, the unresolvable property is various with the distance and sensor observation accuracy. In this paper, we focus on the resolvable property for the group targets. The decision algorithm. The simulation results show that the proposed method can effectively reflect the change of the group target resolution caused by the change of the distance between the target and the radar.