Embodiments of the invention provide an interference-resistant device, method and system applied to a wireless body area network (WBAN). The device is applied to a HUB of the WBAN and comprises an acquisition unit, a determination unit, and a processing unit. The acquisition unit is used for obtaining BAN ID, HUB ID, BAN priority, frequency hopping period, time information use for time alignment and frequency hopping information for calculating frequency hopping sequence of an adjacent WBAN. The determination unit determines whether to carry out conflict avoidance according to the WBAN to which the HUB belongs and the BAN priority and/or channel frequency hopping period of the adjacent WBAN. The processing unit carries out conflict avoidance according to the frequency hopping information of the WBAN to which the HUB belongs and the frequency hopping information and the time information of the adjacent WBAN when the HUB carries out conflict avoidance. By the embodiments, the channel collision probability is reduced, and interference between two adjacent or overlapped WBANs can be well avoided.