Due to the limitation of wireless sensor networks in energy resources and the fact that part of Skyline query results can satisfy the users in many applications, this paper proposes an energy efficient approximate Skyline query processing algorithm to save the energy maximally according to the different requirements of applications. The proposed algorithm can compute an approximate Skyline result set only by making partial sensor nodes transmitting their sensing data back. And it is energy efficient because each sensor node transmits its sensing data back or not only depending on the information of itself, without the comparison with other data. Accordingly, communication cost is greatly reduced and network energy is greatly saved. Extensive experiments in simulation environment indicate that the proposed algorithm can process the approximate Skyline queries in wireless sensor networks energy efficiently according to different requirements of applications.