A medium access protocol—Medium Access Control for Terahertz wireless networks(MAC-T) protocol is proposed in order to realize the networking and communications of ultra-high data-rate wireless local networks based on Terahertz technology. It adopts a star topology and TDMA-CSMA access mechanism. The networking mechanism，the access mechanism, and parameter settings in the proposed protocol are studied in detail. This protocol can assure and facilitate the realization of an ultra-high data-rate communication up to 10 Gbps in Terahertz wireless local networks.