The Wireless Body Area Network (WBAN), which comprises of a set of tiny, invasive/ non-invasive, light-weight, high-energy-efficient biosensors that monitor human health for early diagnosis and therapy, has lately received a lot of interest from researchers. As present and rising tendencies in communications included with the tendencies in microelectronics and embedded system technologies. The existing techniques of IEEE 802.15.4 and IEEE 802.15.6 standards are explored in WBANs. As a consequence, discussed the challenges of MAC layer in WBAN. Secondly, different multiple access techniques along with TDMA, CSMA/CA, Slotted Aloha, and Hybrid are explored in terms of design goals. In literature, several of Medium Access Control (MAC) protocols for WBANs have been suggested for addressing the particular challenges associated with reliability, delay, collision and energy within the new research area. The design of MAC protocols is primarily based on multiple access techniques. Finally, the general parameters of some popular MAC protocols are highlighted as performance metrics of WBANs.