In order to improve the temperature resistance of common oil well cement fluid loss additive，a new quadripolymer fluid loss additive for high temperature cement slurry was synthesized by 2-acrylamide-2-methyl propane sulfonic acid （AMPS），acrylamide（AM），acrylic acid（AA）and N-vinyl pyrrolidone（NVP）. The effect of monomer concentration，monomer ratio and initiator concentration on the performance of fluid loss additive was studied. The temperature-resistance and salt-resistance properties of fluid loss additive and the effect on the performance of cement slurry system were investigated. The results showed that the optimum synthesis condition of fluid loss additive was obtained as follows：15% monomers dosage，monomer composition：60% AMPS，20% AM，15% AA and 5% NVP，initiator，crosslinking agent（N，N-methylenebis acrylamide）and molecular weight regulator（sodium methallyl sulfonate）dosage of 1%，0.15% and 0.8% in terms of total monomer mass respectively，7 pH value，60℃ reaction temperature，4 hrs reaction time. The fluid loss additive had good temperature and salt resistance property，the temperature-resistance capacity was up to 180℃. The API water loss of cement slurry system including 3% fluid loss additive and 36% NaCl could be decreased to 46 mL. At 180℃，the API water loss of cement slurry system including 4% fluid loss additive was 48 mL，thicken time was 308 minutes and compressive strength of cement stone was 32.5 MPa. The AMPS/AM/AA/NVP quadripolymer fluid loss additive satisfied the cementing operation requirements at high temperature.