The present study is aimed to investigate the effects of Chenopodium album (leaves) on the growth of estrogen dependent (MCF-7) and estrogen independent (MDA-MB-468) human breast cancer cell lines. The different solvent extracts (petroleum ether, ethyl acetate and methanol) were assessed for their cytotoxicity using TBE (Trypan blue exclusion) and MTT [3-(4, 5-dimethyl thiazol-2-yl)-2, 5-diphenyl tetrazolium] bioassay. These cells were cultured in MEM (minimum essential medium) medium and incubated with the dilution series of extracts (10–100 mg/ml) in CO2 incubator at 37°C for 24 h. Among the various extracts studied for two cell lines, methanolic extract of C. album (leaves) exhibited maximum antibreast cancer activity having IC50 (the concentration of an individual compound leading to 50% inhibition) value 27.31 mg/ml against MCF-7 cell line. Significant percent inhibition (94.06%) in the MeOH extract of C. album (leaves) at 48 h of exposure and concentration 100 mg/ml (p < 0.05) against MCF-7 breast cancer cell line, indicates the presence of some structural moiety responsible for this observed antiproliferative effect. In vivo study and structural elucidation of its bioactive principle are in progress. Our findings highlight the potential of this plant for its possible clinical use to counteract malignancy development as antibreast cancer bioagent.