In this study, the combination of infrared - hot air dryer was used for drying of button mushroom. The effect of infrared lamp power (150, 250 and 375 W), hot air temperature (50, 60 and 70oC) and hot air rate (1, 2 and 3 m/s) on drying of button mushroom were investigated. The results of infrared-hot air drying of button mushrooms showed that by increasing of lamp power from 150 to 375, the drying rate increased. With the increase in hot air temperature from 50 to 70oC, and hot air rate from 1and 3 m/s, weight loss increased 10.3% and 13.9%, respectively. Also process modeling were done with the genetic algorithm–artificial neural network (GA-ANN) method with 4 inputs (lamp power, hot air temperature and rate, drying time) and 1 outputs for prediction of weight loss. Sensitivity analysis results by optimum GA-ANN showed the drying time of mushroom was the most sensitive factor for controlling of weight loss. The results of modeling by GA-ANN showed that a network with 7 neurons in the hidden layer with sigmoid activation function can predicted the weight loss (R=0.99) of button mushrooms dried by infrared system-hot air method.