Objective: Intraductal papillary-mucynous pancreatic neoplasm (IPMN) represents 0,5 to 9.8 % of all tumors of exocrine pancreas. Our aim was to study nuclear ploidy of malignant and benign IPMNs cells. Method: We studied 20 pancreatic surgical specimens from 5 females and 15 males. We performed histological, morphometrical and ploidy analysis of all specimens. Results: IPMN cells nuclear perimeter and size was higher than in normal pancreatic duct cells. This parameters were higher in malignant noninvasive IPMN than in benign tumor. Nuclear size and perimeter of invasive malignant IPMN were in intermediate position between benign and malignant noninvasive tumor. Mean nuclear ploidy (MNP) of normal ductal pancreatic cells was 2.4c. MNP of benign IPMNs was 2.5c, borderline tumors -3.0c. MNP of noninvasive malignant IPMNs was 5.1c, of invasive IPMNs -4.5c. We also revealed that aneuploidy coefficient (AC) of benign IPMNs was 0 (there weren't aneuploid nuclei in its cells). AC of borderline IPMNs was 0.11. Maximal level of AC was in malignant noninvasive IPMNs whereas AC of invasive IPMNs was lesser. Conclusion: Nuclear morphometric parameters and mean nuclear ploidy level as well as aneuploidy coefficient could be used as additional criteria for determining malignant potential of IPMNs.