For expanding a new way to use wheat straw, the authors conducted an orthogonal （experiment） in order to determine the feasibility of making wheat straw-plastic composites. In this （paper,） the hot-reaction characteristics of wheat straw, plastics （PE, PVC, EVA） and three kinds of wheat straw-plastic composites were examined by Differential Scanning Calorimetry method （DSC）. DSC curves of the monomer and composite materials revealed the distinctions between them, which indicated that some chemical reactions had happened between the wheat straw and the plastic. The paper further analyzed the effects of experimental factors, such as the plastic types, size of wheat straw powder and the ratio of wheat straw to plastic, on the tensile strength of the composite. These results provided references for researching technology for wheat straw-plastic composites.