A mobile ad hoc network (MANET) is a dynamically reconfigurable wireless network that does not have a fixed infrastructure. Because this kind of network uses wireless connections for communication, traditional transport protocol for wired networks is not suitable for MANETs. In this paper, we propose an improved transport protocol (ITP) to enhance the efficiency of the transport protocol in MANETs. In ITP, we use a rate-based transmission scheme with fuzzy logic control to tune the proper data rate. ITP gets the MAC layer information and uses a fuzzy logic controller to estimate the appropriate data rate for transmission. Then ITP uses a feedback scheme to adjust data flow by receiving a feedback packet. The difference between traditional TCP and ITP is that ITP adjusts its transmission rate using the received packet instead of the acknowledgments or lost packets. Simulation results show that the proposed ITP outperforms TCP and ATP.