To address the current lack of systematic methods for constructing virtual models of measurement equipment, a digital modeling method for measurement equipment based on a function-structure-motion composite model is proposed. By analyzing the measurement principle, function, and operational procedure, the measurement capability of the equipment is clarified and a functional model is constructed. The structural composition of the equipment is disassembled, and the components are assembled according to the hierarchical structural relationships to build a structural model. The degrees of freedom and kinematic constraints of the mechanism are analyzed, and the motion mechanisms associated with the functions are established to construct a motion model. A coordinate measuring machine is taken as an example for application verification. The results show that this method can effectively simulate the measurable and reachable workspace, motion trajectory, and interference conditions of the measurement equipment, support reachability analysis and measurement path planning, and lay a technical foundation for simulated measurement and future remote metrology applications.