Objective To evaluate the application value of color Doppler ultrasonography in detecting thoracodorsal thoracodorsal arteriey perforator flap. Methods 31 patients candidate for thoracic dorsal artery perforating flap were included in this study.Before surgery,we used color Doppler ultrasonography to detect the perforating branch,including vascular contorts,diameter,the location of the perforators and surface markers.Results All the 31 pieces of thoracodorsal arteries were examined, 30 case can be detected of the perforating branch; 1 case appeared distortion and variation of blood vessels before surgery,thus changed to other surgery. Conclusions The application of color Doppler ultrasonography provides a direct, and accurate measurement to understand the blood circulation of musculus latissimus dorsi musculocutaneous flap .