In order to optimize the non-homogeneity of the reservoir to improve the effectiveness of acidizing operations, a self-assembled acidizing steering polymer named AHD, was synthesized in this study. Acrylamide (AM), sulfonate monomer (HSY) and octadecyl dimethyl allyl ammonium chloride (DMAAC-18) were used as functional monomers to obtain polymer AHD, which was characterized by FTIR and GPC. AHD could form steering acid system with trimethylstearylammonium chloride（STAC） by self-assembly. The viscosity of this system could increase from 3 mPa·s to 288 mPa·s without crosslinking agent when the addition of AHD and STAC was 1.0 % and 0.2 % (based on the total mass of HCl solution) at 90 ℃. Fresh acid was easier to introduce into the formatio because it had a lower viscosity than the non-crosslinked polymer steering acid’s viscosity. With 1.0 % oil addition, the viscosity of the spent acid after gel breaking was less than 10 mPas, maintaining the benefit of viscoelastic surfactant steering acid could gel break automatically in the situation of oil for backflow. According to the mechanism of the TEM and DLS investigations, Ca2+ encouraged the development of bigger aggregates in the surfactant-polymer self-assembly system, which allowed the steering acid to be diverted.