A novel polyethylene/palygorskite nanocomposite with excellent processability was prepared via in-situ coordination polymerization. A mixed catalyst of TiCl4/MgCI2/AIR(3) was employed. Firstly the Ziegler-Natta catalyst of TiCl4/AlR3 was loaded on the surface of the nanoscale whiskers of palygorskite to prepare the "macromolecular comb". Secondly the MgCl2 catalyst was introduced into the reaction system to prepare the ordinary PE molecular chain. The polyethylene/palygorskite nanocomposites thus obtained possessed excellent mechanical properties.