A laser detecting instrument is disclosed that comprises body, laser head, mechanical arm, delivery device, material receiving device, detecting clamping fixture, laser controller. Said laser head is mounted on the laser lifting device which can make the laser head move along the direction of the Z axis, the laser lifting device is mounted on the body supporting plate, the delivery device, the material receiving device and the detecting clamping fixture are also mounted on the body supporting plate, the mechanical arm includes the mechanical fingers, the Y axis supporting device, the Z axis supporting device, and the mechanical fingers mounted on the Y axis supporting device which makes the mechanical fingers move along the direction of the Y axis, the Y axis supporting device is mounted on the Z axis supporting device which is mounted on the body supporting plate to support the whole mechanical arm. The laser detecting instrument includes the control device which controls the movement of said laser head, the laser controller, the mechanical arm, the delivery device, the material receiving device, the detecting clamping fixture. The invention has high precision in detection, fast speed, flexible setting for parameters, simple and convenient operation, and it has the large market and good economic benefit.