Abstract: The characteristics of the dehydration and power consumption on microwave drying pumpkin slice were obtained, and the mathematical model of microwave drying pumpkin slice through the tests of power consumption and dehydrating of microwave drying on pumpkin slice was developed. By using orthogonal regression test on the effects of 4 factors on 4 indexes, the regressive equations of various indexes, i.e. power consumption, dehydrating rate, the ability of absorbing moisture and quality of appearance were obtained. Through nonlinear programming optimizing the parameters, the better combinations of parameters, i.e. power, slice thinkness, dehydrating rate, load, on various indexes were obtained, significance analysis of parameter difference and synthetical optimization of 4 factors on 4 indexes were conducted, and the better combinations of parameters were obtained.