Partially stabilized zirconia (PSZ) powders were fully densified by microwave heating using a domestic microwave oven. Pressed powder compacts of PSZ were sandwiched between two ZnO-MnO2-Al2O3 ceramic plates and put into the microwave oven. Tn the first step, PSZ green pellets were heated by self-heating of ZnO-MnO2-Al2O3 ceramics (1000 degrees C). In the second step, the heated PSZ pellets absorbed microwave energy and self-heated up to a higher temperature (1250 degrees C), leading to densification, The density of PSZ obtained by heating in the microwave oven for 16 min was 5.7 g/cm(3), which was approximately equal to the density of bodies sintered at 1300 degrees C for 4 h or 1400 degrees C for 16 min by the conventional method. The average grain size of the sample obtained by this method was larger than the average grain size of samples sintered by the conventional method with a similar heating process.