Wideband data link refers to the data link used to distribute reconnaissance intelligence such as images, videos,high-speed data stream information, generally speaking, wideband data link is mostly high-frequency and high-order modulationsignals, more sensitive to IQ imbalance, and wideband data link frequency band is higher, the non-ideal of radio frequencyperformance and devices will cause more serious IQ imbalance problem and performance deteriorates of the communication system.Therefore, aiming at the IQ imbalance problem of wideband data link, an IQ imbalance model is established, the IQ imbalancecompensation method is studied, and a data-assisted IQ imbalance compensation method of wideband data link is designed, whichhas the characteristics of high efficiency, low complexity and easy hardware implementation. Simulation verifies the effectiveness ofthe method.