In a feeding trial with 180 broilers the impact of mycotoxin contaminated maize on growing and slaughtering performance, and on physiological parameters was investigated. Four feeding groups with different levels of contamination were used in the experiment. Feeding groups 1, 2, 3 and 4 were fed with 54.6, 36.4, 18.2 and 0 % uncontaminated and 0, 18.2, 36.4 and 54.6 % highly contaminated maize, respectively. Highly contaminated maize contained 9.8 mg Desoxynivalenol, 1.04 mg Moniliformin, 1.43 mg Beauvericin and 0.105 mg Fumonisin B1 per kg. Other components of the diet were 31.4 % soyabean meal, 4.4 % oil, 3 % maize gluten feed, 3 % grass meal, 0.051 % L-lysin-HCl, 0.141 % DL-methionin, 1.22 % limestone, 1.63 % dicalcium-P, 0.15 % salt, 0.16 % NaHCO3, 0.015 % vitamin premix, 0.040 % trace element premix, 0.080 % cholin-Cl and 0.050 % Monensin-Na. At the end of the growing period (37 days) the chickens of feeding group 1, 2, 3 and 4 had a live weight of 1896, 1942, 1904, and 1943 g and the feed conversion rates were 1.81, 1.77, 1.83 and 1.82 kg/kg LW-gain, respectively. The contaminated diets had no negative effect on live weight gain, feed conversion rate and liver weight, but did significantly (P < 0.01) increase heart weight. The chemical composition of carcass and the physiological parameters of the blood (AST, LDH, triglycerid and cholesterin) were not affected. The experiment shows, that maize contaminated with Fusarium toxins had no negative effects on growing and slaughtering performance and on meat quality (tenderness, juiciness and taste), and on blood parameters. As the present investigation shows, the negative effect of Fusarium toxins has been practically overestimated, and Fusarium toxins were probably unjustifiedly blamed for many problems in broiler production.