A tissue sensor probe and corresponding electromagnetic surgical ablation system are disclosed. The system includes an ablation probe coupled to a generator, a controller coupled to the generator, and a tissue sensor probe coupled to the controller. The tissue sensor probe includes an electrically-conductive enclosure configured to shield a temperature sensor from electromagnetic radiation produced by the ablation probe. At least a portion of the electrically-conductive enclosure is made of a high thermal-conductivity material. A material of high thermal-conductivity is disposed in the electrically-conductive enclosure in thermal association with the thermally-conductive material of the electrically-conductive enclosure. The temperature sensor is disposed in the material of high thermal conductivity so as to electrically isolate the temperature sensor from the enclosure. The temperature sensor provides tissue temperature to the controller, which monitors tissue temperature to determine tissue status and activates and deactivates the generator based on the tissue status.