The utility model provides a domatic angle measurement apparatus, it includes folding plane, folding plane by last plane and lower plane folding joint, go up graphic settings horizontal bubble, go upthe plane and be provided with the resistance wire down between the plane, resistance wire one end is fixed on plane down, the other end passes through last planar becket and spring coupling, the ampere meter passes through becket and resistance wire constitution powered loop, the ampere meter is connected with signal processor. Calculate out resistance wire effective length in the circuit throughthe electric current, by signal processor extrapolate the plane and down the contained angle between the plane be the angle of gradient, make the measured data direct indication come out. This devicehas simple structure's characteristics, and the angle of gradient is measured to the accuracy fast.