Objective: Pericardial effusion (PE) is a common clinical condition that can develop as aresult of systemic or heart disease. In our study, we synthesized the cytopathological andclinical results of patients who underwent pericardiocentesis due to pericardial effusion.Method: A total of 213 patients who underwent percutaneous pericardiocentesis between2007-2017 were included in the study: their cytologic and histopathologic diagnoses werenoted and their relations were examined.Results: Hundred and thirty-two cases were male (61.9%), 81 were female (38.1%) and themean of the study population age was 59.9 (min 13-max 97) years. Hundred and sixty-eightpatients had benign (78.9%), 10 suspicious (4.6%), 3 non-diagnostic (1.4%) and 32 malignant cytologies (15.1%). Benign pericardial effusion was the most common diagnosis.Malignant cytology findings were interpreted as lung carcinoma (n=20: 62.5%), rhabdomyosarcoma (n=1: 3.1%), poorly differentiated adenocarcinoma (n=2: 6.2%), a gastrointestinal system carcinoma (n=4: 12.5%), undifferentiated epithelial tumor (n=1: 3.1%),breast carcinoma (n=1: 3.1%), and unspecified malignant tumor (n=3: 9%). Four (2.4%)of the 168 patients having diagnosis of benign cytology had previously received diagnosis ofa malignant disease, however examination of cytological specimen. Did not reveal anymalignancy. Three (30%) of the 10 patients with suspicious cytology, had received diagnosis of a malignant disease previously.Conclusion: In developed countries, it is reported that more than 50% of the PE’s areidiopathic. The percentage of cancer-associated PE’s is 10-25%. In our study, 78.9% ofour cases had a benign diagnosis, and 15.1% had malignant PE consistent with the literature findings. Cytological sampling in pericardial fluid is a method that can shed light onthe diagnosis of many diseases.