Abstract: While grid-forming converters actively support the inertia and damping of the power grid, the coupling effect between their active power and reactive power leads to power oscillation problems. Moreover, factors such as differences in line impedance, inherent resonances of filters, and parallel operation of multiple converters will further exacerbate the power oscillation issue. To address this, the mechanism of power oscillation triggered by the power-coupling effect of grid-forming converters is first analyzed. Secondly, the loop-reshaping method is adopted to transform the power-coupling multi-input multi-output(MIMO) model of the grid-forming converter into a single-input single-output(SISO) model, and the influence of key control parameters on the operating characteristics of the grid-forming converter is analyzed. On this basis, a power-oscillation suppression strategy for grid-forming converters based on reactive-power feed-forward compensation is proposed, and the corresponding state-space model is established to analyze the influence of compensation control parameters on the stability of the grid-forming converter. Finally, the correctness and effectiveness of the proposed strategy are verified through simulations and experiments.