Disclosures of the present invention describe a coaxial microwave rotary applicator for material processing, mainly comprising: a waveguide unit, a microwave generator connected to one end of the waveguide unit, a bearing unit, a chamber, a rotary shaft, a driver unit, a sampling unit. The bearing unit is connected to the waveguide unit through a non-rotary ring, and the chamber is connected to a rotary ring of the bearing unit, and the microwave generator is configured for supplying a microwave to the chamber. By such arrangements, it is able to uniformly heat a specific material disposed in the chamber by driving the chamber to rotate. It is worth noting that, a user is allowed to clearly observe the processing progress via the sampling unit during the heating process of the specific material.