The aim of this study was to determine the individual and combined toxic effects of MYSTIC 250 EC fungicide (tebuconazole 250 g/l) and lead acetate on the development of chicken embryos. The chicken eggs were dipped in the solution or emulsion of the test materials for 30 minutes on the first day of incubation (day 0). The applied concentration of lead acetate was 0.01% and of fungicide MYSTIC 250 EC was 0.1%. The chicken embryos were examined on day 19 of incubation by the followings: rate of embryo mortality, body mass, type of developmental anomalies by macroscopic examination. The body mass was evaluated statistically by the one-way ANOVA, the embryo mortality and the developmental anomalies was analysed by Fisher test. The body weight of the embryos in all treated groups applied the test items individually or simultaneously was significantly decreased compared to the control group. The embryo mortality was increased statistically in the embryos treated with lead acetate alone or in combination with MYSTIC 250 EC fungicide. The frequency of developmental abnormalities was sporadic in all treated groups. Our teratogenicity study revealed that, the individual toxic effect of lead acetate and tebuconazole containing fungicide formulation(MYSTIC 250 EC) was embryotoxic but not teratogenic in chicken. Based on the results, there is an addition type toxic interaction between tebuconazole containing MYSTIC 250 EC and lead acetate resulted in increased embryotoxicity due to the concomitant exposure.