Data services, especially multimedia services drain battery quickly. Hence, it becomes more and more important to reduce power consumption in order to prolong active time of a mobile station. Three types of sleep mode schemes were defined in 802.16e for power saving. Sleep window size is either fixed or exponentially increased in these schemes. Past researches showed that power saving performance can be improved by carefully adjusting the sleep window size. Past researches also tried to balance the power saving performance and packet delivery latency, which contradict with each other. In this paper, a novel counter-driven adaptive sleep mode scheme is proposed and analyzed. It intends to present a generic and easy-to-implement adaptive sleep window scheme that keeps up with the change of user activity level. This autonomous and adaptive power saving scheme distinguishes itself from all other researches surveyed so far in the literature by minimizing signaling overhead and easily balancing between packet delivery latency and power saving performance according to QoS requirement of established data services.