A floor high-low transition plate comprises a foundation and an arc panel, wherein a fork-shaped mortise without barbs is arranged at the bottom of the panel, two outer sides of the fork head of the mortise are provided with a plurality of corrugations for increasing friction, a groove in the middle of the fork is formed in big end down shape which is convenient to insert a tenon arranged on the foundation, the foundation is made of engineering plastics with certain degree of elasticity, a snapping groove which is formed by two vertical plates and a base plate and has an inner side without barbs is disposed on the foundation, an inserting tenon with a big end up trapezoidal shaped is installed between the two vertical plates, the inserting tenon is slightly bigger than the groove on the mortise, the inserting tenon leads the fork-shaped mortise to expend sideward after being inserted to press on the inner wall of the snapping groove for fixation, when required, the inserting tenon can be drawn out with slight strength and can be reused. The floor high-low transition plate is easy to install and detach, has safe usage and good decoration effect.