To explore the seismic performance of vertical connection joints in modular concrete wall-floor, this study designed and tested three types of joints: monolithic casting, grout anchor connections, and bolt connections under cyclic loading. The research systematically evaluated their failure processes, hysteresis behavior, energy dissipation capacity, and the degradation of stiffness and strength. The test results indicate that regardless of the connection type used, all specimens tended to fail through bending and demonstrated excellent seismic performance, meeting the seismic demands in practical engineering applications. The seismic performance of the vertical connection joints using grout anchor connections was nearly identical to that of the monolithic cast specimens, showing comparable strength, ductility, energy dissipation capacity, and stiffness. However, specimens with bolt connections had lower strength and stiffness than monolithic cast specimens, but exhibited better ductility and enhanced energy dissipation performance compared to those using grout anchor connections and monolithic casting.