Possible Effect of Citrus Limon Juice and Tamoxifen on the Tumour growth mass Indices, Cell Proliferation, Cell Viability and Cytogenetic (Mitotic Index) of Sprague Dawley Rats Induced MCF-7 Breast Cancer Cells was carried using, over one hundred and twenty Sprague dawley rats of 40 days old with average body weight 180-220g were divided into Ten (10) groups with 12 animals per group, group 1 was control, fed only with rat chow and water, group 2 was MCF-7 cell line induced Breast cancer rat alone (BCIR only), group 3 Citrus limon juice (CLJ) at 8.88%, Group 4 Citrus limon juicen (CLJ) at 17.32%, group 5 Citrus limon juice (CLJ) at 25.98%, group 6 was given 0.2mg/kg of Tamoxifen alone, group 7 (BCIR+ CLJ at 8.88%), group 8 (BCIR+ CLJ at 17.32%), group 9 (BCIR+CLJ at 25.98%) and group (BCIR+ 0.2mg/kg of Tamoxifen). Acute and sub – acute toxicity were carried out after the establishment of safety dose following determination of LD50, on the fresh Citrus limon juice, Tumour growth mass Indices were carrying out on weekly basis on the experimental rats, on completion of the administration of the treatments, animals were sacrificed, Blood was collected into Plain and hepariniced bottles simultaneously for Cytogenetic (Mitotic Index) analysis, Tumour tissues were also extracted, passaged and cells were cultured and analysed for Cell Proliferation and Cell Viability assays. Microscopically, it was revealed that DMSO at 1.5% was highly toxic to the MCF-7 cells and other components of media, meanwhile the Citrus limon juice at 8.88%, 17.32% and 25.98% showed minimum cell growth inhibition of MCF-7 cell lines and permit cell viability at 40%, 25% and 10% respectively without any effect on the media components. In conclusion, this study showed that Citrus limon juice posses anticancer activities and does not pose pathological conditions on the body during and after usage, hence it could be used as alternative therapy in the treatment of Breast cancer that are hormonal dependant in similar manner to Tamoxifen.