The invention provides an automatic adjustable sit and reach test device which is characterized in that a supporting sleeve is fixedly mounted on a seat plate and the seat plate is sleeved with a cylindrical gear, and a test table is mounted on the cylindrical gear; the inner bottom of the supporting sleeve is provided with a longitudinal electric cylinder and a longitudinal push rod supporting cylindrical gear, the cylindrical gear can rotate and move up and down in the supporting sleeve, two longitudinal sides of the seat plate are provided with height limiting sliding grooves respectively,a blocking foot plate and a height limiting plate are vertically disposed on the seat plate, and the two ends of the height limiting plate are clamped in the height limiting sliding grooves and can slide; one end of the test table is provided with a laser device and a light-blocking piece sliding groove, the other end of the test table is provided with a returning electric cylinder and a returningpush rod, and the returning push rod is opposite to a U-shaped sliding plate and can push the U-shaped sliding plate to move and return. The automatic adjustable lifting, rotation and automatic testreturn of the sit and reach test device are achieved, quick and continuous batch testing can be performed, the testing efficiency and accuracy are improved, and the measurement, reading and display are integrated.