LAPTM4B was proven to overexpress in hepatocellular carcinoma and relate to differentiation. We immunohistochemically investigated the expression and potential clinicopathological and prognostic significance of LAPTM4B encoded protein, LAPTM4B-35, in extrahepatic cholangiocarcinoma (EHCC) for specimens from consecutive 81 patients. LAPTM4B-35 staining was positive in cancer tissues from 59 patients (72.8%), including 12 with score 1, 22 with score 2 and 25 with score 3. No positive staining was found in non-cancer epithelia. The staining score in cancer tissues was not only significantly associated with TNM staging, histological grade, perineural and lymph node invasion (P<0.05), but also of comprehensive prognostic implications, including integrated estimation with CA19-9. These data established that LAPTM4B-35 positively expressed in a great portion of EHCC and might be a novel molecular maker of progression, invasiveness and poor prognosis.