The single toxicity and joint toxicity of disthylstilbestrol(DES), dibutyl phthalate(DBP)and propyl thiouracil(PTU)to the proliferation of GT1-7 cells were investigated. Methods The dose of DES was 0.1,1, 10,0 and 1 000 μmol/L, the dose of DBP was 0.01,1, 10,0 and 1 000 μmol/L, and the dose of PTU was 0.000 1,0.01,1,100 and 1 000 μmol/L. The dose of joint toxicity were DES(0.1-1 000 μmol/L), DBP(0.01 μmol/L) and PTU(0.000 1 μmol/L). The cell counting Kit-8 was used to evaluate the viability of GT1-7 cells under DES, DBP and PTU alone or combined exposure. Results When DES and DBP exposed alone, the viability of GT1-7 cells increased at first and then decreased with the higher dose. Compared with the control group ,the viability of GT1-7 cells exposed to PTU increased and maintained at a certain level. When the concentration of DES, DBP and PTU was below 10,0 and 1 000 μmol/L, the viability of GT1-7 cells was above 90%. When DES and DBP, DES and PTU combined exposed to GT1-7 cells, the viability was increased first and then decreased with the increase of DES concentration. When DBP and PTU combined exposed, then cell viability had the same change. When 0.01 μmol/L DBP and 0.000 1 μmol/L PTU added to 0-10 μmol/L DES, the cell viability increased obviously, and the difference was significant(P＜0.05).But when concentration increased to 100 μmol/L DES, the cell viability was decreased from 80% to 4%, and the difference was significant(P＜0.05). Conclusion When DES, DBP and PTU was exposed to GT1-7 cells, the cell proliferation increased at first and then decreased. When they were combined at a certain concentration, it showed a joint effect of cell proliferation on GT1-7 cells.