The  lone and combinational effects of cytotoxicity  of selected medicinal plants detected  by using MTT assay, XTT assay, LDH assay and Tryphan Blue dye exclusion assay on MCF7 cell lines. Combination of two plant extracts shows more anti–cancer activity, because the combined extract may contains more  phyto–consituents involved in anti–cancer activity of both plants. Thus our findings makes stronger that the extracts of Simarouba glauca and Annona muricata is more effective solution for the discovery of novel herbal formulations for cancer therapy.