A polymer gel microsphere profile control agent [P(AA-AM-C(18)DMAAC)@SiO2] with a multilayer assembled structure was prepared by combining multiple assembly and nanocomposite technology via inverse emulsion polymerization and precipitation polymerization using silicon dioxide (SiO2), acrylamide (AM), and acrylic acid (AA). The structure of the gel microsphere was characterized by SEM, FTIR, and TGA. The results indicated that the multilayer assembled polymer gel microsphere was successfully prepared. The introduction of SiO2 enhanced the strength of the profile control agent, and the outer hydrophobic association polymer octadecyl dimethyl allylammonium chloride (C(18)DMAAC) changed the temperature resistance and salt resistance of the polymer by adjusting the polymer composition. Further, the influences of C(18)DMAAC dosage in P(AA-AM-C(18)DMAAC)@SiO2 at different temperatures on the water absorption ratio of the gel microsphere was studied and concluded that at C(18)DMAAC to P(AA-AM)@SiO2 mass ratio of 1.25:1, the water absorption performance of the profile control agent was optimal. Moreover, the microsphere of the P(AA-AM-C(18)DMAAC)@SiO2 shows the characteristics of absorb water slowly at low temperatures and quickly at high temperatures. And the prepared microsphere has a certain salt tolerance, and the viscosity of the P(AA-AM-C(18)DMAAC)@SiO2 microsphere increases slowly, so it could be used as a promising profile control agent in future. POLYM. ENG. SCI., 59:1507-1516 2019. (c) 2019 Society of Plastics Engineers