The invention discloses a concrete temperature stress tester capable of directly measuring the concrete deformation and a testing method for the concrete temperature stress tester. The tester comprises a machine body, an upper deformation measurement system, an upper sensor and an upper extension rod, wherein a plurality of movable templates are arranged on the machine body, and the movable templates are matched to define a mold cavity for placing concrete blocks; the upper deformation measurement system comprises two upper pre-buried rods which are located above the mold cavity, and pre-buried components suitable for stretching into the concrete blocks are respectively arranged at the lower ends of the two upper pre-buried rods; the upper sensor is arranged at the upper part of one pre-buried rod; and one end of the extension rod is connected with the upper sensor, and the other end of the upper extension rod is connected with the other upper pre-buried rod. According to the concrete temperature stress tester provided by the embodiment of the invention, concrete deformation can be directly measured, and measurement accuracy is high.