The invention discloses a method and system for adjusting the sensitivity of an offshore wind plant current collecting system. The method comprises the steps that the annual fault frequency of each device in the system and the annual fault repairing time of each device are firstly obtained so that the fault rate of each device can be determined; rated power of all fans in the system is obtained and the equal output power of topology is determined according to the fault rate of each device and the rated power of each fan; the equal outage rate of the system is determined according to the equal output power of the topology; the sensitivity of each device is determined according to the equal outage rate of the system and the fault rate of each device and the proportion of each device occupied in the system is adjusted according to the sensitivity of each device. According to the method and system for adjusting the sensitivity of the offshore wind plant current collecting system, the influence on the reliability of the topology by the fault rate of the devices of a cable, a switch, the fans and the like is comprehensively considered, sensitivity analysis is conducted on the corresponding device influencing the reliability of the topology, and the method and device have the positive meaning to the economic cost reduction and fault opportunity cost reduction of the current collecting system under different allocation plans, and have certain reference value for engine design and research of the current collecting system.