This paper proposes a motion detection method based on Gaussian mixture model for detecting the moving objects in old film sequences. Conventional motion detection techniques can hardly be applied to the old film sequences due to the influence of intensity flicker. The proposed method combines an adaptive mixture method with a motion detection. The intensities of a particular pixel along the temporal direction are modeled as the Gaussian mixture model. The adaptive mixture method can automatically determine the number of components in the Gaussian mixture model and estimate the parameters of each Gaussian component. Then the components with small weights are chosen as the components corresponding to the moving objects. Experimental results show that the proposed method can effectively detect the moving objects in old film sequences.