To solve the problem of friction pendulum system without pull-out resistance under external load excitation， based on electromagnetic principles and semi-active control ideas， an electromagnetic chuck friction pendulum composite isolation system （ECFPS） based on electromagnetic force combined with traditional friction pendulum is proposed. The structural characteristics and energy dissipation mechanism of the composite isolation system are introduced， and theoretical formulas for electromagnetic suction force， equivalent stiffness， period， and equivalent damping ratio of ECFPS are derived based on electromagnetic princi? ples. The ECFPS model is established. A 1∶3 scaled ECFPS specimen is designed and fabricated to investigate the hysteresis per? formance under different input currents， vertical loads， and displacement amplitudes. The effects of different currents on the anti uplift performance are investigated. The experimental results show that the theoretical values are in good agreement with the experi? mental values， which verifies the correctness of the theoretical formula derivation. The changes in equivalent stiffness and unit cy? cle energy consumption are significant， with the maximum variation amplitude of 19.81% and 28.16%， respectively. As the cur? rent of the electromagnetic suction cup increases， the anti pull performance of the ECFPS system improves， achieving the vertical resisting pull function of the system.