The invention discloses a microwave sintering method for a SiC ceramic roller. The microwave sintering method comprises the following steps: 1) putting a green SiC ceramic roller body in an insulation apparatus and then placing the green SiC ceramic roller body and the insulation apparatus into a microwave resonant cavity together; and 2) starting a microwave source, adjusting microwave input frequency, carrying out slow heating until humidity elimination and smoke evacuation is finished, then continuously adjusting microwave input frequency, carrying out rapid heating until reflection power is stable, carrying out heating at a heating speed of 20 to 30 DEG C/min to a sintering temperature, maintaining the temperature for 5 to 15 min, then adjusting microwave input frequency and carrying out cooling to room temperature so as to obtain the SiC ceramic roller. The microwave sintering method for the SiC ceramic roller realizes rapid sintering of the SiC ceramic roller, substantially improves uniformity and stability of the performances of a sintered material, effectively avoids the phenomenon of local surface warping of a roller at a fire hole frequently occurred during conventional sintering, improves sintering yield of the SiC ceramic roller and has the advantages of short sintering time, conservation of considerable electric energy and suitability for industrial rapid production.