The basic search algorithm toimplement Motion Estimation (ME) in the H. 263 encoder is a full search.It is simple but time-consuming. Traditional search algorithms are fast, but may cause a fall in image quality or an increase in bit-rate in low bit-rate applications. A fast search algorithm for ME with consideration on image content is proposed in this paper. Experiments show that the proposed algorithm can offer up to 70 percent savings in execution time with almost no sacrifice in PSNR and bit-rate, compared with the full search.