Carrying agents in solid acid systems are susceptible to dilution by formation water during transport to the formation, resulting in poor acidification of solid acids. Based on this, in this paper, a hydrophobic associative thickener (PAAOD) with dilution resistance was prepared by aqueous solution polymerization using acrylamide (AM), 2-Acrylamido-2-methylpropane sulfonic acid (AMPS), methylacryloxyethyl trimethyl ammonium chloride (DMC) and octylpolyoxyethylene ether methacrylate (OEMA). as raw materials. The structure of PAAOD was characterized using Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance hydrogen spectroscopy (1H NMR). The dilution resistance, shear resistance and retardation properties of PAAOD were investigated by means of performance tests such as apparent viscosity, rheology and acid rock reaction rate. The results of the study show that: The monomers were all involved in the polymerization and the PAAOD polymerization was successful. The apparent viscosity of 0.8 wt% PAAOD was maintained at 63.39 mPa·s after shearing for 2 h at 130°C and a shear rate of 170 s-1, showing good temperature and shear resistance; The PAAOD solution was subjected to dilution resistance experiments, and the rate of viscosity loss was 43.75 % for twofold dilution at room temperature (25°C) and 44.80 % for twofold dilution at high temperature (90°C), which showed good resistance to dilution, and after standing for a certain period of time, the loss of viscosity of PAAOD was reduced with a certain degree of restorative properties; The acid rock reaction rate of PAAOD at 130°C was 0.06 mg/(cm2·s), which proved that the polymer had good retardation properties. Therefore, thickening agent PAAOD has good application prospects in deep and ultra-deep wells.