Abstract: Wheat straw fiber/recycled polyethylene (WF/rPE) composites were preparaed with Shaanxi Guanzhong WF and rPE as the raw materials, using the method of extrusion and molding. The effects of maleate grafted polyethylene (MAPE), maleate grafted polyethylene wax(MAPE wax) and γ-aminopropyltriethoxysilane(KH550) and MAPE wax content on the mechanical properties, moisture absorption, thermal stability and interface performance of WF/rPE composites were studied; The chemical structure of WF and the tensile profile of WF/rPE composites were analyzed by FTIR and SEM. The results show that the mechanical properties of WF/rPE composites with MAPE wax are the best, when the content of WF and MAPE wax are 40wt% and 2wt%, the tensile strength and flexural strength of the WF/rPE composites reach a maximum of 15.0 MPa and 23.8 MPa; When the content of MAPE wax is over 2wt%, the mechanical properties and moisture absorption of WF/rPE composites decrease. The TG result shows that the addition of different interfacial modifiers has no significant influence on the thermal stability of WF/rPE composites; The FTIR analysis shows that the silane coupling agent KH550 can react with the hydroxyl group in WF. The SEM analysis shows that the addition of MAPE wax to the WF/rPE composites interface is better than the addition of MAPE and KH550 WF/rPE composites.