The invention relates to a system for testing the comprehensive heat conductivity coefficient and specific heat capacity of a rock-soil body. The system comprises a heating device and a measuring device, wherein the heating device comprises a heat preservation water tank, an electrical heating rod, a water pump, a heat preservation water inlet pipe, a heat preservation water return pipe, a heat exchanger tube and a balance valve, and the measuring device comprises a rock-soil body temperature sensor, a fluid temperature sensor and a flowmeter. The electrical heating rod is arranged in the heat preservation water tank, the water pump is arranged on the water inlet pipe, the flowmeter and the balance valve are arranged on the water return pipe, and the two ends of the heat exchanger tube are respectively connected with the water inlet pipe and the water return pipe. The invention simultaneously discloses a testing method of the system for testing. With the system, the disturbance and damage which are caused by a laboratory test method to the original structure of the rock-soil body are overcome; the defect that a heat probe method is not long enough is overcome; and the defect that the convention vertical buried pipe rock-soil thermal response test cannot test the thermal-physical characteristic parameters of all the layers of the rock-soil bodies is made up. The system is simple and easy to operate during field tests, and is low in cost. The thermal-physical characteristic parameters which are obtained through utilizing the theory to invert are accurate and reliable.