The influence of a humic preparation on the morphological and biochemical composition of the blood of ducklings was studied. A control and two experimental groups of day-old ducklings were formed to conduct the experiment. The birds of the 1st experimental group were additionally fed the drug in 100.0 ml/kg of feed to the main diet, the 2nd experimental group - 150.0 ml/kg. Blood for laboratory analysis was collected at one day, 14, 28, 42, and 56 days of age. It was found that by the end of growing, the birds in the experimental groups had an increase in total protein in the blood by 6.9 - 7.5% compared to the control, and the amount of glucose increased by 6.4 - 10.1% against the background of a decrease in the amount of urea and bilirubin. The levels of uric acid and cholesterol in the blood changed slightly. The indicators of the morphological composition of blood have improved due to an increase in the number of erythrocytes by 6.8 - 8.7%, hemoglobin - by 5.2 - 7.6%. Normalization of the functional state of the ducklings ’bodies increased the bird’s safety over 56 days of rearing.