In mobile ad hoc networks (MANET), the IEEE 802.11 DCF protocol is commonly used for the medium access control layer (MAC) protocol to reduce the number of the collisions and contentions. Mobile nodes have to wait for data transmission to be completed before they send data to anothers. As a result, performance degradation results from such limitations in the DCF mechanism. In this paper, we propose an overlapping data sub-channel method. The overlapping data sub-channel method can use a data sub-channel when the sender and receiver is currently using the same data sub-channel. In order to make the overlapping data sub-channel method work, we use the multiple channel technique to solve the interference problem. From the simulation results, our proposed method results in a better throughput than the IEEE 802.11 DCF method by about 45%. The result shows that our proposed methods are capable of improving throughput in MANETs.