The aim of this study was to evaluate the antioxidant properties of R. pimpinellifolia and its cytotoxic effect against human colon (WiDr), liver (HepG2) and lung (A549) cancer cells compared with a normal fibroblast (BJ) cell line. The antioxidant properties of extract was determined using spectrophotometric methods, while the cytotoxic effect of extract was evaluated using MTT assay. The total phenolic content, total flavonoid content and reducing power values of extract were calculated as 16.4 +/- 0.4 mg gallic acid equivalent, 5.2 +/- 0.2 mg quercetin equivalent and 34.3 +/- 2.4 mg trolox equivalent per g sample, respectively. Although the extract exhibits selective cytotoxic effect on three cancer cell lines in a dose-dependent manner compared to BJ cells, the highest selectivity index value (2.7-fold) was obtained for the WiDr cell line. In conclusion, this is the first study to demonstrate the cytotoxic effect of R. pimpinellifolia on cancer cells. To demonstrate the molecular mechanism of this cytotoxic effect and to carry out in vivo studies may be a guide for future clinical studies.