<p>Weakly cemented soft rock (WCSR) is characterized by poor cementation, argillization (after encountering water), and strong rheology, which leads to the rheological deformation of the surrounding rock is led. To investigate the creep characteristics of WCSR under the action of different water contents (<i>w</i>), the multistage unloading confining pressure creep tests were conducted using the GDS HPTAS creep triaxial apparatus. According to the damage mechanics theory, the water damage variable <i>D</i>_<i>w</i> and the stress damage variable <i>D</i>_<i>σ</i> were defined, and the water–force coupling damage variable<i> D</i> was established. A novel water–force coupling damage variable <i>D</i> was introduced into the Abel dashpot constitutive equation based on the equivalent stress method, and a new nonlinear damage viscoplastic element was established. Subsequently, a four-element fractional-order creep damage model was constructed based on the fractional-order differential theory. By fitting the creep experimental data of soft rock under the action of different water contents, it is evident that the four-element fractional-order creep damage model possesses considerable advantages in characterizing the entire process of creep deformation in soft rock, and the model parameters are few and easy to obtain. The research results can provide a theoretical basis for predicting the creep deformation characteristics of WCSR under the action of different water contents and help prevent creep damage that leads to instability in surrounding rock underground roadway engineering.</p>