The overall objective of this research was to improve the basic knowledge about the important parameters of the microwave drying of leafy herbs. Specific objectives were to determine the effects of microwave power density on drying time and drying rate, improve the product quality in terms of colour, compare the fitting ability of several drying equations to express the drying kinetics of mint leaves with the most suitable drying model and to describe the whole process in a general drying model by embedding the effects of microwave power density on the coefficients of the best fitting model for the purpose of simulation and scaling up of the process. The microwave drying of mint (Mentha spicata L.) leaves have been studied at different operating parameters of drying using mathematical models. Experiments were conducted using seven levels of microwave power density, 4, 5, 6, 7, 8, 9 and 10 W g -1. Eleven mathematical models describing drying kinetics have been investigated.