It is well known that CSMA/CA shows good performance in case of a few devices and low traffic rate but the more the number of devices and traffic rate increase, the more the performance decreases dramatically because of too much contention among the devices. It leads to increasing the retransmission rate it, as a result, brings about high energy consumption and if there are hidden terminal, performance would get worse. In this paper, we propose polling-based channel access mechanism to address above problems basically raised from CSMA/CA mechanism. From the simulations, the proposed scheme has increased throughput and energy efficiency than existing CSMA/CA scheme as it avoids the repeated collisions in heavy traffic loads, and also increased throughput and decreased delay than round-robin polling scheme by unifying the procedure for the coordinator to discover the devices which have a data frame transmitted.