The invention provides an emergency power control method and system of an offshore wind power flexile and direct access system. The emergency power control method comprises the steps of receiving a control signal sent from a system dispatching center by a communication system built in advance; starting a corresponding emergency power control method according to the type of the control signal, wherein the emergency power control method can act on a land braking resistor and/or offshore wind power field AC system; and arranging the land braking resistor at a DC outlet of a land converter station. The characteristic that a flexible DC active power can be rapidly and independently adjusted is utilized, an emergency power control method is designed, the power injected to a main grid system canbe effectively adjusted, and the offshore wind power control flexibility is improved.