Abstract: A magnetic material fixing structure of motor rotor including multiple overlapping silicon steel plates. An outer circumference of each silicon steel plate is recessed to form multiple receptacles at equal intervals. A magnetic material is disposed in each receptacle. The receptacle has two lateral faces, a bottom face and an opening opposite to the bottom face. Each of adjoining sections of the two lateral faces and the bottom face is formed with a dented section dividing the lateral faces and bottom face of each receptacle into multiple resilient plates. When inlaying the magnetic material into the receptacle, the resilient plates are deformed to resiliently tightly clamp the magnetic material.