Underwater Acoustic Wireless Sensor Network (UAWSN) use acoustic signals to transmit data. Acoustic signals in underwater environment have high bit error rate, long propagation delay and limited bandwidth. Another constraint in UWASN is energy. Due to these constraints, design of energy and bandwidth efficient and propagation delay aware MAC protocol is a great challenge in UWASN. Underwater sensor nodes have to share medium. The main role of the MAC layer protocol is to decide when a node accesses a shared medium and to resolve any conflicts between nodes. In this paper, we evaluate the performance of three famous underwater MAC protocols UWAN-MAC[1], R-MAC[2] and Slotted FAMA[3] in terms of packet drop rate, throughput and energy consumption. We have used Aquasim simulator to evaluate MAC protocols. تفاصيل المقالة