Abstract: Considering the control channel bottleneck issue and hidden terminal issue for multi-channel MAC in Ad-hoc networks, a new multi-channel MAC with the Low Control Overhead (LCO-MAC) is proposed. Different from the multi-channel MAC mechanism based on the channel usage table, for LCO-MAC reference to the Request To Send/Clear To Send (RTS/CTS) channel assignment mechanism proposed by Meshhadany, each data channel is mapped to a time slot of the control section, but the difference is that LCO-MAC does not restrict the sending time of the RTS, and can send data once obtainning the channel. Simulation results show that LCO-MAC not needing too much control information for channel reservation provides an effective solution to the control channel bottleneck and multi-channel hidden terminal issue, the network throughput is also significantly enhanced.