Introduction: FNAC, which is a minimally invasive procedure, has developed as the most accurate and cost-effective initial method for guiding the clinical management of the patients with breast lesions. The International Academy of Cytology (IAC), Yokohama system for breast fine needle aspiration cytology(FNAC) established a uniform, tired reporting system for breast FNAC specimens. Using this system, the cytopathologist can communicate breast FNAC interpretations to the referring clinician. Based on this objectives of our study is to standardize the reporting system of breast lesion by FNAC. To assign all reported breast lesions in one of the five diagnostic categories as defined by Yokohama system to maintain the uniformity. To correlate with histopathology whenever possible. To assess the risk of malignancy(ROM). Materials and Methods: Following institutional scientific and ethical committee approval, this study was undertaken in the Cytology division of Department of Pathology, Kidwai Memorial Institute of Oncology, over a period from1-dec-2019 to 30-may-2021. This was a descriptive study. All smears from FNAC of breast lesions were interpreted according to IACY okohama system. Results: A total of 260 cases of breast lesions were taken during the study period. The demographics constituted 98.1%females and1.90% males with an age range of 13-81years and a mean age of 48.9. The most common lesions were malignant (52.3%), while benign constituted 28.8%. Histopathological analysis were available for 148/260cases. Conclusion: FNAC is a reliable, well tolerated diagnostic modality which can be used in diagnosis of breast lesions. Following the IAC Yokohama system, FNA is a useful tool and requires specific training & ongoing experience. Therefore this newly proposed IACY okohama system for reporting breast cytopathology is a simple system that allows greater diagnostic clarity and, consequently, better communication between pathologist and treating clinician, also helps in predicting the ROM.