At present， it is generally believed that offspring of bipolar disorder（ BDoff） is a high-risk population with bipolar disorder. Studies have shown that BDoff suffer from cognitive impairment to varying degrees， and the mechanism may be related to genetic and biological factors， but it has not been clarified. These cognitive impairment is not caused by single factor， as the damage mechanism may be related to gene polymorphism， immune inflammation， the brain structure， etc. This paper reviews the cognitive impairment and its possible mechanism in the BDoff.