The aim of this study was to determine the individual and combined toxic effects of MYSTIC 250 EC fungicide (tebuconazole, 250 g/l) and cadmium sulphate on the development of chicken embryos. The chicken eggs were dipped in the solution or emulsion of the test materials for 30 minutes before starting of incubation. The applied concentration of cadmium sulphate was 0.01% and of fungicide MYSTIC 250 EC was 0.1%. The chicken embryos were examined on day 19 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 were analysed by Fisher test. Our teratogenicity study revealed that the individual toxic effect of cadmium sulphate and tebuconazole containing fungicide formulation (MYSTIC 250 EC) were embryotoxic. Developmental abnormalities were observed sporadically either single or concomitant treatment. Based on the results there is a possibly additive toxic interaction between the cadmium sulphate and MYSTIC 250 EC that can highly reduce the viability of the embryos or can lead to extinction of wild birds.