The invention relates to a downhole tool flux distribution control device for automatically and vertically drilling used in the field of oil and natural gas exploration and development; the invention is arranged in the upper cavity of the actuating mechanism of a system for automatically and vertical drilling and includes an upper round distributing disc and a lower round distributing disc that can rotate oppositely. The upper distributing disc is connected with the torque generator of a control system by a coupler and can rotate oppositely with the lower distributing disc under the drive of the torque generator. The upper distributing disc is connected with the coupler by a straight key and is locked by a locking cap by adopting a mode of thread fastening. The upper distribution disc can move coaxially in a certain range. Under the control of the control system, the torque generator drives the upper distributing disc to rotate relatively to the lower distributing disc by the coupler; the fan-shaped through hole of the upper distributing disc can be alternatively connected through with the three through holes of the lower distributing disc and a drilling liquid for driving a piston is led to be reasonably distributed by controlling the opposite rotation of the two, thus realizing the accurate control of the downhole tool flux distribution control device for automatically and vertically drilling to the straightening force of the actuating mechanism.