Aim: The aim of this study was to classify breast fine needle aspirates according to the IAC Yokohama system and determine the frequency of each category within the system and assess the risk of malignancy and determine diagnostic value of cytology by comparing them with pathohistological findings. Study design: A cross-sectional study with historical data Participans and methods: This study included 432 participants who underwnet a pathohistological examination of breast lesion from January 1st, 2019 until December 31st 2023 at Clinical institute for clinical cytology at Clinical Hosiptal Centre Osijek, after having previously undergone a cytological examination of the same lesions. Analysed smears were fixed in the air and coloured with May-Grünwald method or cytospin preparations were made using Shandon Cytospin and centrifuged at 1500 rpm for 3 minutes. The cytological findings were classified according to the Yokohama classification into categories C1-C5 and compared with the pathohistological diagnosis. Results: According to the cytological diagnosis, the most frequently recorded diagnoses are malignant and suspicious finding. There is a significant difference in the distribution of patients according to cytological diagnosis and pathohistological findings. Patients classified as C4 and C5 in the cytological diagnsis have significantly more malignant findings according to the PHD, while C1, C2 and C3 are more often benign. There are no significant differences in the distribution of PHD findings concerning the gender of the patient. Conclusion: The study showed that there is a significant difference in the distribution of cytological diagnoses according to the Yokohama classification system compared to pathohistological diagnoses. Cytological diagnoses of suspicious and malignant are significantly more often associated with malignant histopathological diagnoses.