The propagation properties of incoherent light beams through a one-dimensional photonic crystal with a defect layer are investigated by means of incoherent theory and transfer matrix method. The influence of incoherence and the incident angle on the transmitted lateral shifts of defect modes and the lateral shifts on the reflecting surface of the photonic crystal are discussed. The transmitted and reflected lateral shifts are both enhanced with the strengthening of coherence. In comparison with the pass band of one-dimensional photonic crystal without a defect layer, it is found that the defect layer will increase the transmitted shift. In different incoherent conditions, the shift of defect modes is always lager than that of other waves in pass band.