The invention discloses a polar modified polymer material and a preparation method thereof, and the material comprises the following raw materials in parts by weight: 50-100 parts of polypropylene (PP), 10-100 parts of LLDPE (linear low-density polyethylene), 5-20 parts of maleic anhydride grafted polyethylene, 10-40 parts of inorganic materials which are processed by silane coupling agent, 2-10 parts of toughening agent and 0.5 part of 1010 antioxidant. By adopting the maleic anhydride grafted polyethylene with polar groups, the product can have certain polarity, thus improving the surface coating property of the product; by adding the inorganic materials which are processed by the silane coupling agent, the inorganic materials are fully compatible with mixture of the polypropylene and the LLDPE (linear low-density polyethylene), thus improving the hardness of the product; adding the toughening agent can improve the toughness of the product and the bonding strength with metal; and the polar modified polymer material of excellent anticorrosion performance, strong adhesion and good use technology is prepared.