This paper presents an area-filtering algorithm for antialiasing technique of computer graphics images. It can be applied to low-resolution image, which the aliasing effect is more visible. Unlike supersampling technique, which costs too much to do well, this technique is simple and suitable for VLSI implementation. Without changing the current PC-based graphics-hardware architecture, this `technique costs little overhead and improves the image quality of aliasing images5-10 dB on the average.