ABSTRACT Spatial intra prediction has been added recently to the latest video coding standard H.264/AVC. In the intraprediction of H.264/AVC, there are 9, 9 and 4 prediction modes for 4 × 4, 8 × 8and16× 16 blocks, respectively.Prediction signals are generated by using one or several reference pixels. The value of a reference pixel is copiedas the prediction value. In some prediction modes, we c alculate a weighted mean by averaging several pixels.The same prediction value is copied to several of the pixels lying in the prediction direction. However, if originalimage has patterns like gradations, the residual energy could increase which would result in low coding eciency.In this paper, we propose a new intra prediction that generates prediction signals with a spatial gradient to dealwith this problem. Simulation results show that it improves the picture quality and reduce the bit-rate by about0.14 dB and 1.0 % on average for CIF sequences, respect ively. It is also con“rmed that our method is eectiveat high bit-rates.Keywords: H.264/AVC, intra prediction, spatial gradient, gradation, coding ec iency improvement