In order to develop a new type of slick water reducer，the long-chain end-group hydrophobic associating polymer HPAM-L was prepared from acrylamide（AM），hydrophobic monomer dodecyldimethylallylammonium chloride（C₁₂DMAAC）， sodium acrylate （NaAA） and homemade long-chain hydrophobic initiator 2，2'-azobis（isobutyl）dodecamidine hydrochloride （AIBL）. The structure and properties of HPAM-L were characterized by infrared spectroscopy，nuclear magnetic resonance spectroscopy， Ubbelohde viscometer， fluorescence spectrophotometer and rotational rheometer. The resistance reduction performance of HPAM-L solutions with different concentrations was measured by using fracturing fluid friction tester. The results showed that the relative molecular weight of HPAM-L was 7.43 × 10⁶，and the critical association concentration was 1—1.5 g/L. HPAM-L had good temperature resistance and shear stability. The aqueous solution of HPAM-L had a wide linear viscoelastic region. The higher the concentration，the more obvious the elastic characteristic was. The maximum drag reduction rates at the solution mass fractions of 0.075%，0.086%，0.1% and 0.15% could reach 71.6%，73.1%，73.3% and 74.1%，respectively， showing good drag reduction performance.