The aim of the study was to compare morphometric characteristics of different types and grades of breast cancer. Morphometric analysis was performed using the SFORM software (Vamstec, Zagreb) on the May-Grünwald-Giemsa stained fine needle aspiration cytology (FNAC) breast tissue specimens. The study included 42 patients diagnosed with breast carcinoma by breast smear FNAC at Merkur University Hospital during the 2001-2005 period. Postoperative tumor histopathology and semi-quantitative tumor grading by the method of Elston and Ellis' showed invasive ductal carcinoma grade I in 10, invasive ductal carcinoma grade II in 9, invasive ductal carcinoma grade III in 13, and invasive lobular carcinoma in 13 patients, the latter also including a subtype of invasive tubulolobular carcinoma. The following parameters were assessed by use of Statistica 7.1 and chi2-test: tumor area, circumference, maximal radius, minimal radius, convexity, length, width, elongation, nucleus/cytoplasm ratio, and shape factor. Morphometric analysis yielded statistically significant differences among all study groups (p < 0.001). Morphometric parameters showed significant individual correlation with tumor type and grade, whereby the area, convexity and circumference were most significant at both nuclear and cellular level.