Background: Breast cancer is the most commonly diagnosed cancer in women worldwide and the most frequent cause of cancer death in women in low-income countries. Cytotoxic chemotherapy drugs called taxanes alter the cellular mechanisms that allow cancer cells to divide their microtubules. In a typical cell cycle, microtubules are formed by the cell at the start of division and disassembled after the cell stops dividing. Taxanes stabilize the microtubules, preventing them from breaking down normally. This causes the cancer cells to stop dividing, potentially slowing the growth of cancer or killing the cells. Taxane causes neutropenia and thrombocytopenia, as well as fatigue, nausea and vomiting, hair loss, diarrhea, mouth ulcers, and muscle pain. According to the literature, chemotherapy causes nuclear atypia and other cellular changes in buccal mucosa cells. There was no published data regarding the effect of taxane on buccal mucosa cells. This study aimed to detect cytomorphological changes among breast cancer patients receiving taxane chemotherapy. Materials and methods: This is a comparative cross-sectional study conducted during the period from December 2022 to February 2024, involved 50 buccal smears from breast cancer patients included as a case group versus 50 buccal smears from apparently healthy females. All smears were processed through conventional cytological methods. Results: Forty percent of patients have had a family history of breast cancer. We observed that in 80% of patients with advanced age (46 years old and older), our results indicated that there was a significant statistical difference between cases and controls regarding cellular changes in buccal mucosa. We also observed an increase in the significant correlation of cellular changes and the number of taxane doses, as the p value was less than 0.05. Conclusion: We concluded that taxane chemotherapy may cause buccal cellular changes as the incidence of nuclear atypia, infection, and degenerative changes is higher in cases than in controls.