The utility model provides a negative screw thread locking assembly assembling calibrating apparatus. The apparatus comprises a fixing base and screw sleeves. One end of the fixing base is provided with a fixing groove; the screw sleeves are arranged at the two sides of the fixing base; the fixing base is used for connection with the interface of an electric connector contact piece; and the screw sleeves are used for connection with negative screw thread locking screws. In one embodiment, the fixing base employs a pin type fixing base, and the screw sleeves employ first hexagonal screw sleeves. In another embodiment, the fixing base employs an inserting hole type fixing base, and the screw sleeves employ second hexagonal screw sleeves. The apparatus provided by the utility model can be adaptive to assembling and calibrating of positive screw thread locking assemblies with different specifications, facilitates connection with positive screw thread locking assemblies, improves the assembly connection primary assembling success rate and the product connection reliability, and decreases the production cost.