the thickening agent PAMSDV was synthesized by homogeneous polymerization in aqueous solution，using AM, AMPS, DAC and NVP as raw materials. Through investigating the effect of the dosage of PAMSDV and cross-linking agent on the viscosity of temperature controlling viscosity acid (TCA), the optimal recipe of TCA was obtained, which was composed of 5% PAMSDV and 1.25% cross-linking agent (cross-linking agent comprised methane and Al₂(SO₄)₃ at mass ratio of 1:1), and dissolved in 20% hydrochloric acid. The viscosity of the TCA system changed with temperature. The viscosity reached the maximum value of 2400 mPa·s at the temperature of 70℃. Although the viscosity decreased a little at the temperature of 90℃, the viscosity was 1100 mPa?s, which displayed a certain performance of high-temperature resistance. In addition, the TCA system had other excellent performances such as compatibility, salt resistance and acid-rock reaction retardation. After the gel of the TCA was completely broken, the viscosity of the gel breaking fluid was 8 mPa?s.