A series of 80 patients with chronic lobular hepatitis (CLH) was reviewed clinically and histologically to demonstrate etiology, clinical presentation, course, and prognosis of this disorder. Data from our study indicate that CLH in Taiwan is a disease of viral origin, mostly hepatitis B (67.5%) and some non-A, non-B. It occurs predominantly in young males (81.3%); frequently commences as acute viral hepatitis (57.5%); and has clinical and laboratory features similar to convalescent viral hepatitis or even indistinguishable from full-blown acute viral hepatitis. Clinical and histological follow-up study indicate that CLH may extend for several years with remissions and relapses. No evidence of progression to cirrhosis was observed at least in a 4½-year period of follow-up. It is concluded that CLH is a persistent but nonprogressive disease although the number of non-A, non-B CLH is too small to ascertain its nonprogressive course. The prognosis is generally good, and no specific therapy is required.