A method of human motion detection by using graph cuts was proposed.Firstly,we built an adaptive background mixture models in the hue-saturation-value(HSV) color space,and got the background quickly.Secondly,we computed the difference and eliminated shadow.Finally,we represented the images as an 8-connectivity network graph,and segmented it through minimum cutting.Based on several experiments,we compared single model with mixture model background,4-connectivity neighbor with 8-connectivity one and morphological operation with graph cut.The result shows that a clean and smooth human segmentation can be gotten quickly,effectively and robustly by using the proposed method based on graph cuts in practice.