PIVKA-II (Protein Induced by Vitamin K Absence-II or Antagonist-II) is an abnormal form of prothrombin that is synthesized in the state of vitamin K deficiency or in the presence of its antagonist that inhibits the activity of vitamin K-dependent carboxylase. Elevated concentrations of PIVKA-II in neoplastic cells of hepatocellular carcinoma (HCC) occur as a result of a damaged process of carboxylation of the prothrombin precursor. In the complex process of hepatocarcinogenesis PIVKA-II promotes cell proliferation, tumor growth and the occurrence of metastases. After its discovery, this molecule became the subject of research, and its analytical features, such as satisfactory sensitivity and specificity, make it an optimal tumor marker in the diagnosis, monitoring and treatment of HCC, a disease with a high incidence and high mortality rate. The aim of this study was to assess the acceptability of the analytical method for the quantitative determination of PIVKA-II in human serum on the Snibe Maglumi 800 analyzer through the verification process before it becomes a part of the routine work in the laboratory of the Clinical Hospital Dubrava. The chemiluminescence immunoassay (CLIA) was used for determination of PIVKA-II concentration, and verification of the method was performed according to CLSI EP15-A2 guidelines using two control samples whose concentration was measured in triplicate during 5 days of measurement. The verification process included an assessment of precision, accuracy, measurement uncertainty and a comparison with the method implemented in Clinical Hospital Center Rijeka. The achieved results for precision, accuracy and mean total error met the set acceptance criteria. The results of the comparison of the tested method with the existing method shown by the Bland-Altman representation and the Passing-Bablock regression analysis do not show the existence of either constant or proportional error that would be statistically significant. However, a discrepancy was observed in the results of some patients due to the application of different methods of determination of the same analyte, which is proof of the incomparability of immunochemical methods. In order to avoid the risk of different clinical interpretation of the results, it is necessary to always monitor each patient using the same method in the laboratory. Based on the verification results, it is concluded that the newly introduced method of quantitative determination of PIVKA-II in serum meets the set acceptance criteria and can be used in routine laboratory work.