In this study 223 samples (75 blood samples, 70 Litter &78 Feed of broiler chickens) were collected from Dakahlia, Sharkia and Domiate Governorates, Aspergillus species (Flaves 87.4% and Niger 11.4%) was only detected in litter and ration. Also, estimation of aflatoxin and ochratoxin Out of examined samples 78 (31.39%) were positive for aflatoxin and ochratoxin. Positive aflatoxin in broiler feed (15.3%), litter (30%) and chicken sera (20%) while positive ochratoxin in broiler feed (11.5%), litter (18.57%) and in chicken sera (4%). One day old, Ross 308 chicks (125), weight 40 gm were obtained from Dakahlia Poultry Hatchery. All birds were vaccinated against Newcastle disease and gumboro disease. Broilers were divided into five groups (25 chicks/each), Gp (1) broilers feed ration free from mycotoxin all over the experimental period, Gp (2) broilers feed on ration contaminated with aflatoxin B1 (25 ppb) all over the experimental period, Gp (3) broilers feed ration contaminated with aflatoxin B1 (12.5ppb) all over the experimental period, Gp(4) broilers feed ration contaminated ochratoxin (5.5 ppb) all over the experimental period and Gp (5) broilers feed ration contaminated with (2.75 ppb) ochratoxin allover the experimental period. Broilers in all groups were weighted every week for determination body performance parameter. Mortality rate was recorded. blood sample were taken for estimation hematobiochemical parameters Chickens supplemented with ration contaminated with aflatoxin in tested dose showed mortality rate (32% Gp 2 and 16% Gp 3) while for ration contaminated with ochratoxin from 28% (Gp 4) and 20%(G5). Groups fed contaminated rations with Mycotoxin (aflatoxin and ochratoxin) induce significant decrease in body weight and body weight gain from the second week up to 5th week post treatment and increased FCR in broilers. In the other hand chicken supplemented with mycotoxin (aflatoxin and ochratoxin) showed significant decrease in total protein, albumin and heterophile phagocytic activity beside significant increase in serum AST, ALT, bilirubin, uric acid and creatinine all over the experimental period. In conclusion mycotoxin contamination in feed and liter in broiler farms cause high economic losses (significant decrease in body performance) as well as immunosuppression post vaccination and hepatorenal damage.