The paper studies the detection of the event of the objects left behind in intelligent video surveillance systems,and gives a complete set of test schema. The multipleGaussian model is used for the detection of the moving objects,and its adaptability well solve the impact of changing background frame.The  MeanShift algorithm is used for tracking the moving targets,which expands the scope,not only limited scope.The feature of Sevenband Moment Invariants well describe the target, through which support Vector Machine can identify the objects. The experimental results prove the effectiveness of the method.