The invention discloses a cardiac CT and ultrasound image registration method based on salient region area matching, and the method mainly solves a problem of low registration precision and low speed in the prior art. The method comprises the steps: 1) pre-processed CT and ultrasound images respectively serves as a reference image and a floating image, and a gray-scale feature pyramid model and a neighbourhood mean difference feature pyramid model of the two images are respectively established; 2) saliency maps of the reference image and the floating image are respectively generated based on above two pyramid models, and the saliency maps are binarized; 3) for the binarized results, regions of interest are extracted according to region area features, coarse registration based on region centroid distance and precise registration based on ICP algorithm are performed on the regions of interest, and registration parameters are obtained; 5) according to the registration parameters, rotation and translation transformation is performed on the floating image, and a registration result is obtained. According to the invention, the method has high registration precision and fast speed and can be used for real-time registration of preoperative CT image and intraoperative ultrasound image.