Contention-Based Forward (CBF) has proven to achieve a very good performance in mobile ad-hoc networks. Compare with other greedy forward algorithm, CBF is much more robust and have low maintenance network overheads. On the other hand, the main issue of CBF is to avoid packet duplication. Duplication is very easy to occur due to the hidden nodes problem. In this paper we introduce an area partition-based suppression algorithm for CBF in mobile ad-hoc networks. This algorithm sets the transmission area of a node into two areas: suppression area and none-suppression area. In the none-suppression area, the algorithm still use the SS-CBF (Sender Suppression-CBF) algorithm, in the suppression area, this paper will use a new equation to avoid packet duplication. The result shows that the new protocol could reduce the network overheads and do not cost extra transmission time.