<p>The construction and development of a creep constitutive model for rock and soil is an important for predicting the long-term stability of landslides. To predict the nonlinear process of the creep behaviour of mudstone under hydro-mechanical coupling and apply it to engineering, a new creep model considering hydro-mechanical coupling damage was constructed, and a corresponding explicit finite element algorithm was developed. Then, triaxial creep tests and long-term stability analyses of landslides were carried out in ABAQUS. The results revealed that the numerical outcomes of the hydro-mechanical coupling damage creep model align well with the creep test curves and that the effect of hydro-mechanical coupling on the mudstone time‒strain relationship is reasonably reflected by the developed model, especially during the nonlinear process in the viscoelastic stage. A parameter sensitivity analysis revealed that the nonlinear process in the viscoelastic stage clearly increases with increasing hydration damage <i>D</i>_<i>w</i>, and the influence of the viscosity coefficient <i>η</i>₁ on the strain is greater than that of the elastic coefficient <i>G</i>₁. Compared with the InSAR monitoring results, the landslide displacement calculated by the improved creep model is similar to the monitoring results. The creep model constructed and developed has strong applicability in the finite element analysis of the long-term stability of landslides. These research results provide a basis for evaluating and predicting the long-term stability of landslides.</p>