The aim of the study was the evaluation of HER2 status in ovarian tumors. Material consisted of 158 patients with ovarian tumors treated in Center of Oncology since 1995 to 2005: 128 cases were entered to further analysis. Two methods were applied: immunohistochemistry (IHC) for the evaluation of HER2 receptor and fluorescence in situ hybridization (FISH) for the assessment of HER2/neu gene amplification. Into the analysis with the immunohistochemistry method were qualified 54 ovarian cancers, 59 borderline tumors and 11 benign tumors. Into the analysis with FISH method were qualified 53 ovarian cancers, 62 borderline tumors and 11 benign cysts, the other were disqualified because of technical reasons. The analysis of HER2 receptor by IHC resulted in different rate of positive cases according to different criteria of interpretation and varied between 7.4 and 51.85% in ovarian cancer and between 0 and 33.9% in borderline tumors. HER2/neu gene amplification assessed with FISH was observed in 7.55% of ovarian carcinomas and 3.23% of borderline tumors. There was no correlation between positive cases in both methods – IHC and FISH. The work is the part of grant realized with KBN support and the final goal is to compare the HER2 status with clinical outcome in patients with ovarian tumors.