Natural products have been the target for cancer therapy for several years but there is still a dearth ofinformation on potent compounds that may protect normal cells and selectively destroy cancerous cells. Thepresent study was aimed to evaluate the cytotoxic potential of n-butanolic leaf extract of Annona muricata L.on WRL-68 (normal human hepatic cells), MDA-MB-435S (human breast carcinoma cells) and HaCaT (humanimmortalized keratinocyte cells) lines by XTT assay. Prior to cytotoxicity testing, the extract was subjected tophytochemical screening for detecting the presence of compounds with therapeutic potential. Their relativeantioxidant properties were evaluated using the reducing power and DPPH*radical scavenging assay. Since mostof the observed chemo-preventive potential invariably correlated with the amount of total phenolics present inthe extract, their levels were quantified and identified by HPLC analysis. Correlation studies indicated a strongand significant (P <0.05) positive correlation of phenolic compounds with free radical scavenging potential. Theresults revealed that the extract was moderately cytotoxic to normal cells with a mean IC50 value of 52.4 μg whencompared with those obtained for cancerous cells (IC50 values of 29.2 μg for MDA-MB-435S and 30.1 μg forHaCaT respectively). The study confirms the presence of therapeutically active antineoplastic compounds in then-butanolic leaf extract of Annona muricata. Isolation of the active metabolites from the extract is in prospect.