The present disclosure provides an anti-loosening screw pair and an anti-loosening screw component. The screw pair includes a first screw component provided with a first screw thread and a second screw component whose outer wall surface is provided with a second screw thread. The first and second screw components are in threaded connection. In a direction of the first screw component being screwed into the second screw component, sides of the first and second screw threads pressing against each other are formed into force-bearing fitting faces respectively, and opposite sides thereof are formed into non-force-bearing fitting regions respectively. At least one of the force-bearing fitting faces and the non-force-bearing fitting regions of the first and the second screw components is provided with a stopper so as to prevent radial displacement between the first and the second screw components.