The invention relates to generator set power oscillation comprehensive diagnosis method and system. The method comprises the steps of (1) acquiring real-time data; (2) determining the power oscillation of the generator set; (3) determining the oscillation type; (4) positioning a disturbance source; and (5) determining an oscillation reason, and adopting an emergency response strategy. An emergencyresponse strategy can be timely and accurately adopted for oscillation reasons, so that the problems that in the prior art, the source detail analysis and comprehensive diagnosis capacity of generator set power oscillation is not enough, and the forced oscillation control capacity is not enough are solved.