Due to assembly technology requirements and the introduction of connection seams, the numerical simulation and analysis of prefabricated concrete structures face new challenges. The trade-off between computational efficiency and simulation accuracy becomes increasingly apparent. Based on the general finite element software ABAQUS, in this study a multi-scale modelling approach is used to simulate and analyse the seismic performance of monolithic precast concrete frame structures. Firstly, the correctness of the interface connection method for multi-scale units is validated using experimental data from monolithic precast concrete beam and column substructure. Then, static pushover analysis and dynamic elastic-plastic time-history analysis are performed on the multi-scale model featuring a monolithic precast concrete frame structure. Subsequently, the seismic response and damage of this model are compared with those of a cast-in-place concrete frame structure. The results show that multi-scale modeling effectively improves calculation accuracy and reduces calculation costs. It aptly replicates the failure characteristics of monolithic precast concrete frame structure and overall seismic performance. Compared with the cast-in-place structure, the monolithic precast frame structure exhibits lower lateral stiffness and superior ductility under unidirectional static forces. When subjected to a rare 7-degree earthquake, their seismic performance remains comparable, with a modest 3.8% increase in maximum top-floor displacement. Furthermore, this study underscores the applicability of the multi-scale modelling method in the analysis of prefabricated concrete structures.