In this study pesticides with different chemical structures (dichlofluanid, endosulfan, simazine, tolylfluanid and triallate) were examined for their potential cytotoxic effect on proliferative activity of cell cultures of mammalian origin. Cell lines Madin-Darby Bovine Kidney (MDBK), Rabbit Kidney (RK13), Porcine Kidney (PK15), and semicontinual line of Bovine Embryonic Pulmonary Cells (BEPC) were used in the study. From these cell cultures cell proliferative activity was suppressed most intensively in PK15 culture by endosulfan (10−1 - 10−6 M). The least effect on cell proliferation in all cell cultures tested, with the exception PK 15 (10−1 - 10−2 M), was recorded after simazine exposure. On the basis of IC50 values the cytotoxic effect was: dichlofluanid (IC50 = 10−3.94 M) > tolylfluanid (IC50 = 10−3.69 M) > endosulfan (IC50 = 10−3.24 M) > triallate (IC50 = 10−3.12 M) > simazine (IC50 = 10−1.78 M). The comparison of average IC50 values of cell cultures revealed that the most sensitive cell lines were PK15 (IC50 = 10−3.27 M) and RK13 (IC50 = 10−3.21 M), whereas MDBK (IC50 = 10−2.55 M) and BEPC (IC50 = 10−2.52 M) were less sensitive to pesticide exposure.