The invention relates to a device and method for detecting the wheel center depth of an aluminum wheel cast blank, the device includes a roller way tray, a position sensor, a frame, a CCD camera, a programmable controller and a laser distance measurement sensor, an upper servo-cylinder, a motor support, a servo-motor and a lower servo-cylinder. The invention has the following advantages: the method for automatically detecting and identifying the wheel center depth of an aluminum wheel cast blank is utilized for the identification and classification of wheel cast blanks, so as to reduce the influence of large casting dimension tolerance on the machining dimension tolerance, increase the acceptability rate of products from the automatic machining unit, ensure that the production line automatically runs with high quality and quantity and also reduce the labor intensity of operators.