The insulation properties of 6 newly developed roof insulation pads were analyzed on the basis of measurements in tunnels. The test results showed that the insulation ability of the 5 out of the 6 pads was better than that of the tested straw curtain, which means that they can be used alone to enable vegetable to grow during wintertime in the area where the light intensity is high enough and outside temperature is not lower than -10℃. The structure and waterproof performance, together with the necessity of the reflective aluminum in insulation pads were discussed. Suggestion on the structure to improve insulation performance was proposed as well.