PURPOSE: Patients with biliary atresia (BA) suffer from progressive liver damage, even after successful Kasai portoenterostomy (KPE). The purpose of this study is to analyze the relevance of follow-up percutaneous liver biopsy (LBx) and long-term prognosis of patients with BA. METHODS: This study included patients with BA who were born between 1983 and 2005 and survived with their native liver until 10 years of age. Patient characteristics, laboratory data and Child-Pugh score at the time of LBx, and native-liver survival (NLS) and complication-free survival (CFS) in patients with mild (F0-F2) or severe fibrosis (F3, F4) on follow-up LBx were retrospectively analyzed. RESULTS: Forty-three patients were gathered in this study and the most recent LBx was performed at age 21.1 ± 2.9 years. Thirty-three patients had mild fibrosis and ten patients had severe fibrosis on follow-up LBx. Long-term NLS and CFS were significantly worse in patients with severe fibrosis. Among those patients, 18 patients had follow-up LBx between the ages of 6 and 12 years, and CFS were significantly worse in patients with severe fibrosis. CONCLUSIONS: We found that patients with BA with severe liver fibrosis on follow-up LBx had worse long-term survival and a higher rate of progression of complications of BA.