The intermittency of the microwave drying speed can be modulated according to the initial moisture content of capsicum by using PLC. The microwaves desiccators can be heated evenly using a rotating parabolic guided wave design. Each processing unit is composed of a microwaves desiccator and a cooling pipe, which can be flexibly added or reduced according to the need. The entire product line is designed as a serpentine tunnel structure, making the device structure more compact and reducing the occupied area. The PLC and optical fibre temperature controller are the main controlling system, which can realize the production automation. The experimental results show that, the drying efficiency and quality are greatly improved with a yield of over 98%, which fulfills the experimental requirement.