Serum levels of leucine amino peptidase (LAP) was studied along with bilirubin, aspartate transaminase (AST), alanine transaminase (ALT), gamma glutamyl transpeptidase (GGT), alkaline phosphatase(ALP) and the ratio of AST/ALT and GGT/ AST in 26 healthy subjects and 82 patients with hepatobiliary malignancies of which 12 ware with hepatoceUular carcinoma, 12 with liver metastasis, 8 with obstrucUve jaundice, S with carcinoma of gall bladder, (; with carcinoma of pancreas and 7 with periampulisry carcinoma. 24 Of the 62 patients studied had jaundice and 28 were without jaundice.LAP as compared to the other enzymes AST, ALT, GGT, ALP and ASTIALT ratio and GGT/AST ratio showed 100% elevation in obstructive jaundice, carcinoma of gall bladder and pancreas and pedampullary carcinoma, 91.7% elevation in hepatocellular carcinoma and 83.3% elevation in liver metastasis. On comparing the levels of these enzymes in non jaundiced and jaundiced groups, LAP was elevated in both jaundiced and non jaundiced groups in 96.8% and 92.9% cases respectively whereas the other enzymes AST showed increase from (;7.9% to 100%, ALT from 21.4% to 83.3%, GGT from 71.4% to 88.4% and ALP from 82.1% to 100% in non jaundiced and jaundiced groups respectively indicating that LAP rises in hepatic dysfunction due to hepatobiliary malignancy whereas the other liver function enzymes showed increased hepatic dysfunction due to hepatobiliary malignancy with the onset of jaundice thereby indicating that LAP is a better indicator of hepatobiliary malignancy as compared to other enzymes.The quantitative methods used for determination are reliable, accurate, simple, rapid and cost effective and therefore have better application in a clinical setting.