Abstract: In order to understand the damage effect of zearalenone（ZEN） on liver structure and function, 75 270-day-old Hailan pink layers were randomly divided into 3 groups, each with 25 chickens. The blank control group was fed the full basal diet, and the test groups Ⅰ and Ⅱ were fed with 1,2 mg/kg ZEN mixed with the full basal diet respectively; and those groups were fed continuously for 90 days and then killed. Serum was collected from 6 laying hens in each group to detect liver function, the visually observed and scored of liver disease, and paraffin sections were used to observe the histological changes of the liver. The results showed that compared with the blank control group, the activity of aspartate aminotransferase（AST） in the serum of the laying hens in the test group Ⅰ was extremely significantly increased（P＜0.01）;in the test group Ⅱ,aspartate aminotransferase, alanine aminotransferase（ALT）,alkaline phosphatase（ALP） activities were extremely significantly increased（P＜0.01）,and the contents of total protein（TP） and albumin（ALB） were significantly reduced（P＜0.05）. Compared with the blank control group, the lesion scores of the laying hens in the test groups Ⅰ and Ⅱ increased extremely significantly（P＜0.01）;in the liver pathological tissue sections, the liver of the laying hens in the test group Ⅰ showed vesicular steatosis, while in the test group Ⅱ,it was dominated by hepatocyte necrosis and fibrosis. The results suggested that ZEN can severely damage the liver structure, cause liver cell degeneration, necrosis and fibrosis, and cause corresponding liver function decline.