Due to the limitation of computing complexity, it is difficult to apply the H.264 deblocking filter to low-end terminals. Although some technologies to optimize it have been proposed, the complexity is still high for real time implementation. Considering that deblocking filter is applied to all of the vertical and horizontal edges of 4times4 blocks but only some of them actually need to be filtered , in this paper, based on previous encoding or decoding information, we propose a novel deblocking filter algorithm to reduce complexity of exist algorithms by skipping quantities of needless edges. The experimental results show that our proposed algorithm has better performance in subjective video quality and time efficiency compared to JM 10.2 algorithm.