The results showed that at low pressure and moderate microwave heating (120 W), the drying rate is high and the quality of the mushroom is also good. At low microwave power(60 W), a good quality of the mushroom was obtained at the cost of a slow drying rate whereas at high microwave power (240 W) or at atmospheric pressure condition, ineffective drying was observed along with the formation of large voids and the entrapment of moisture inside the sample.