Friction is a non-negligible factor in the nonlinear modelling process of magnetorheological (MR) hydro-pneumatic springs. It is difficult for the usual nonlinear models to reflect the influence of friction on their mechanical properties. Therefore, this paper establishes a nonlinear model of MR hydro-pneumatic spring considering the influence of friction. In this paper, the traditional nonlinear modelling does not consider the influence of friction, and the reflected dynamics cannot fully express the nonlinear characteristics. Firstly, the mechanical properties of MR hydro-pneumatic springs are subjected to comprehensive testing, and the impact of friction on their mechanical properties is analysed thoroughly. Then the nonlinear model of MR hydro-pneumatic springs taking into account the effect of friction is established by combining the Bouc-Wen model and the Stribeck friction model. Lastly, parameter identification of the nonlinear model under varying currents was carried out on the basis of the outcomes from mechanical property tests. Results from numerical simulations demonstrate that the constructed nonlinear model is in good accordance with the results of mechanical property tests, and can precisely depict the nonlinear characteristics of the MR hydro-pneumatic spring while reflecting its frictional properties.