Objectives: This study assessed the effects of chemotherapy on haematological and biochemical profile of breast cancer patients undergoing chemotherapy in the Tertiary Care Teaching Hospital. Methods: The study comprised sixty histopathological proven female breast cancer patients at Omega Cancer Hospital, GVPIHC & MT Teaching Hospital in Visakhapatnam. All subjects were divided into four groups: a control group of 60 healthy females of similar age, a group of 60 patients diagnosed with breast cancer and scheduled to start chemotherapy (treatment with anticancer agents) and recorded their demographic, clinical and therapeutic data. Blood was collected for biochemical analysis and for haematological profiles for day 1, day 21 and day 42 of their chemotherapy cycles. Results: Majority of the participants was within 30-75 years, married, overweight and had informal employment. The results showed that, there was a significant decrease in the mean values of haemoglobin, platelet count, neutrophile count and lymphocyte count during different successive cycles of treatment (p<0.05) but the TWBC count mean value was insignificantly variable during the successive cycles of anticancer treatment (p>0.05). The results were insignificant with Na+ and K+ ion concentration between the control and breast cancer individuals. From this study, we found that the parameters like AST, ALT, ALP, Urea, Creatinine and uric acid were significant biochemical markers in breast cancer patients. Conclusion: Chemotherapy produced significant adverse effects such as anaemia, neutropenia, leukopenia, thrombocytopenia, and hepatic dysfunction as a side effect of treatment due to disturbed levels of haematological and biochemical parameters.