Abstract: To improve the thermal conductive properties of the linear low density polyethylene (LLDPE),the aluminum nitride (AlN) particles surface-modified by titanate coupling reagent (NDZ-105) were added into LLDPE and AlN/LLDPE thermal conductive composites were prepared through the powder blending method.The effects of AlN and NDZ-105 content on the thermal conductive property of the composites were discussed.DSC analysis results showed that AlN could enhance the crystallinity of the composites.Results of mechanical properties revealed that the thermal conductive property of the composites increased with the increase of AlN content,and the thermal conductivity coefficient λ came up to 0.883 4 W·(mK)-1 with 50% mass fraction of AlN,being three times of that of pure LLDPE.The thermal conductive property of the composites was further improved after the surface treatment by NDZ-105.