In recent years, the wireless mobile markets are witnessing an unprecedented growth. High-quality video service will be greatly needed as one of the hottest wireless multimedia services in the future generation wireless networks. In this paper, a novel content-based distortion control scheme is proposed to provide higher quality of the wireless video services. Our scheme adopts rate-distortion optimization techniques in state-of-the-art video coding standard H.264/AVC. In order to improve the subjective video quality in the process of encode, we create three visual distortion sensitivity models to minimize the perceptual distortion. We arrange more bits to visual distortion sensitive macroblocks during rate-distortion optimization process. The perceptual distortion in these regions is thus efficiently controlled with a relatively higher rate. Meanwhile, rate balance is achieved by allotting fewer bits to macroblocks that are perceptually less sensitive to distortion. Experiments results show that the subjective qualities of encoded video are improved without compromising PSNR.