Broadcasting is a basic data propagation technique, which has a number of applications such as route discovery and address resolution. While data broadcasting has many gains, it introduces some problems known as broadcast storm problems, which causing a lot of contention, collision and redundant retransmission. Our objective is to reduce the number of rebroadcast. A good probabilistic broadcast protocol can achieve high save rebroadcast. We propose a probabilistic approach that calculates the rebroadcast probability according to the number of neighbour's nodes when nodes move according to different mobility models and compare it with simple flooding, adjusted probabilistic flooding and dynamic probabilistic flooding schemes. Simulation results show our improved approach performs better than simple flooding, adjusted probabilistic flooding and dynamic probabilistic flooding.