Abstract: On the basis of orthogonal test for the mix proportion, the single factor test of wheat straw is carried out. The effects of wheat straw dosage on the performances of insulation mortar are studied, such as dry density, compressive strength, flexural strength, folding pressure ratio, line shrinkage ratio, coefficient of heat conductivity and water absorption rate. Test results show that with straw dosage increasing, the dry density, compressive strength, flexural strength and folding pressure ratio of thermal insulation mortar first increase, then decrease. The coefficient of thermal conductivity decreases, and the thermal insulation performance enhances. When the straw content is 24%, the various performance indexes can meet the basic requirements of Ⅱ type insulation mortar except the dry density. For the insulation mortar with wheat straw, the coefficient of thermal conductivity is relative to the water absorption rate, and the correlation coefficient is 0.934. The water absorption rate of thermal insulation mortar can estimate the coefficient of thermal conductivity, which provide a basis for further optimization study for the mix proportion of the glazed hollow beads insulation mortar with the wheat straw.