The utility model provides a rate gyroscope bracket positioning device for carrier rocket shell section assembly. Wherein the sliding rail is arranged on the base, and the movable support is connectedto the sliding rail and can move. The front end face and the rear end face of the movable support are each connected with a drill plate through a bolt, the two drill plates are parallel to the sliding rail and extend in the direction away from the movable support, the rate gyroscope support is arranged between the two drill plates, a plurality of drill holes are vertically formed in the drill plates, and construction holes are formed in the end face, close to the rate gyroscope support, of the movable support. The tool is simple in structure and accurate in positioning, the assembling precision of the rate gyroscope support can meet the requirement that the included angle between the surface normal and the quadrant datum plane is not larger than 20 ', and the tool requirement is met.