The invention discloses a voltage compensation-based grid-connected inverter control method for a marine electrical system, and belongs to the field of a control method for a grid-connected inverter of a marine power grid. Extraction of positive and negative sequence voltage components is realized in three-phase voltage imbalance of the marine electrical system by an orthogonal signal generated by an orthogonal signal generator of a generalized integrator; meanwhile, a single synchronous coordinate system phase-locking ring is added after a positive sequence voltage signal; the output frequency can dynamically correct the resonant frequency of the generalized integrator, so as to realize self adaption between the resonant frequency of the generalized integrator and the frequency of the marine power grid; in addition, a voltage feedforward control method is adopted, compensation to a grid side imbalance voltage is realized, and anti-interference capability of the system on the power grid voltage distortion is improved; and when the marine power grid voltage is imbalanced, the output power fluctuation can be effectively suppressed, thereby ensuring the stable operation of a sensitive load of the marine electrical system.