A method for detecting vascular sclerosis is revealed. Firstly set a cuff on a human hand. Then inflate the cuff and later deflate the cuff. Next measure a pressure of the cuff and generate a pressure sensing signal. Process the pressure sensing signal to generate a processed signal and convert the processed signal. Then calculate a systolic pressure and a diastolic pressure according to the converted processed signal and also obtain a vasodilation constant. Thus a hardening of blood vessels is detected according to the vasodilation constant.