The invention discloses an angle 
fine tuning device used for tracking small 
angular variation. The angle 
fine tuning device comprises a shell with sliding rails at two sides and a hole respectively at the 
front and back ends, a first articulated shaft transversely penetrating through the sliding rails at the two sides and having a threaded hole in the middle, a second articulated shaft articulated with the first articulated shaft through an articulation piece, and a rotating member fixed at the upper end of the second articulated shaft, wherein one end of the rotating member is articulated with one end of the shell; a motor is fixedly arranged on a worm gear 
reducer and is arranged at the other end of the shell; a screw rod permeates through the bearing in the holes at the 
front and back ends of the shell and the threaded hole in the middle of the articulated shaft, and the output shaft of the worm gear 
reducer is connected through a shaft coupler; the motor rotates to drive the screw rod to rotate; the screw rod drives the first articulated shaft to move along the sliding rails; the rotating member rotates around the articulated place at one end of the shell; and an inclination angle dial can display a rotated inclination angle. The angle 
fine tuning device used for tracking the small 
angular variation can fine-tune the rotating member between 0 degree and 90 degrees, has a simple structure, runs steadily and is capable of reading an angle instantly.