Cholesterol 7α-hydroxylase (Cyp7a1) plays a crucial role in the synthesis of cholic acid and cholesterol catabolism. In this study, Cyp7a1 expression in goose liver was identified for the first time using differential display reverse transcription PCR. This study used real-time PCR and quantified the transcript levels of the cyp7a1 gene under different feeding conditions. In overfeeding, cyp7a1 expression by the liver was lower than that seen for normal feeding and the same result was observed for the Cyp7a1 protein level. The cholesterol level in serum and liver was higher in the overfed group. This study suggests that low-level expression of Cyp7a1 is associated with the formation of goose fatty liver.