The dynamic mechanical properties of basalt affected by microwave were investigated by performing dynamic compressive tests using the SHPB system. Meanwhile, the thermal damage of the treated basalt was characterized by ultrasonic non-destructive testing and nuclear magnetic resonance technology. The results show that with the increase of microwave power and exposure time, the P-wave velocity, dynamic compressive strength and elastic modulus decrease continuously, and the dynamic failure mode tends to be a more complex fracturing. The increase in microwave power and exposure time can enhance the temperature difference and transfer coefficient among minerals, hence intensifying the rock damage induced by thermal shock.