Abstract: Facial expression synthesizing method based on traditional image morphing will not take effect when synthesizing a facial expression image from an expression image with mouth closed and an expression image with mouth opened and teeth showed.In order to overcome this shortage,a novel image morphing method is proposed for image and animation synthesis of facial expression.In this method,the concept of mask image is brought in and the morphing method of mask image is presented,and then the formula of traditional image morphing is revised.The idea of this method is easy to understand and the method steps are simple.This method can effectively produce morphed images.Experimental results show that this method can naturally and livelily synthesize facial expression images from an expression image with mouth closed and an expression image with mouth opened and teeth showed.At this point,this method outperforms other existing facial expression synthesis methods based on traditional image morphing.