Real-time segmentation of moving objects in image sequences is a fundamental step in many vision systems including intelligent visual surveillance and visual traffic analysis.Moving object detection has two key problems presently，one is the accuracy of background modeling，and the other is the disturbance from moving shadows.This paper presents a real-time background subtraction and moving shadow detection method based on Unscented Kalman Filter(UKF)，and constructs the whole frame for moving object detection.Background and moving shadow are modeled firstly.Then，dynamic character of pixel value is analyzed through frame to frame differencing and background differencing，and moving shadows are detected using luminance and chromatic cues of shadow.Finally，model parameters are updated online using UKF，and real-time segmentation of moving objects are completed.Our method exceeds existing ones at background maintenance speed，moving detection effect，and it has simple computational procedure.The experiments demonstrate the effectiveness and practicality of this method.