Abstract The expansion liner hanger has great advantages over the traditional slip liner hanger. Therefore, scholars at home and abroad have carried out extensive research on the expansion liner hanger, but there are few researches on the optimization design of the rubber cylinder of the expansion liner hanger. How to select the size and material of the rubber cylinder is very important to the suspension performance of the expansion liner hanger. Based on the Ø245 mm × Ø178 mm expansion liner hanger as the research object, the condition of the changes under the wall thickness and friction coefficient, using the finite element analysis software of rubber cylinder elongation rate, stress conditions are numerically simulated. The results show that when the wall thickness of the rubber cylinder is t = 1.5 mm, the elongation rate of the rubber cylinder is 2.14 mm, and then the elongation rate of the rubber cylinder increases rapidly with the increase of the wall thickness, and the growth of elongation rate slows down when the wall thickness is t ≥ 3.0 mm. The contact stress of the inner and outer walls of the rubber cylinder increases with the increase of the wall thickness, and the contact stress of the inner wall of the rubber cylinder fluctuates, and the fluctuation tends to be gentle when t ≥ 2.5 mm, and the residual stress of the rubber cylinder is uniformly distributed when t ≥ 2.5 mm. When different friction coefficients (0.05, 0.1, 0.15, 0.2, 0.25, 0.3) were taken between the rubber cylinder and the outer casing, the elongation rate of the rubber cylinder was negatively correlated with the friction coefficient, and the average contact stress on the wall was positively correlated with the friction coefficient. The results of this paper provide guidance for the design and material optimization of the rubber cylinder in the expansion liner hanger.