The aim of the work is to study the effect of drugs Abiopeptide and Ferropeptide on histomorphological indicators of muscle tissue and internal organs (liver, heart, spleen) of guinea fowls. The experiment was carried out in the vivarium of the Department of Parasitology and Veterinary Sanitary Expertise of the Moscow State Academy of Veterinary Medicine and Biotechnology named K. I. Scriabin. Of the guinea fowls of the breed Zagorsk white-breasted speckled, acquired at the daily age at the Zagorsk experimental-breeding farm, on the principle of analogues, taking into account the weight, three groups of 15 heads each were formed. Guinea fowl of the first group were the control and received the basic ration. The second and third groups from the age of 5 days received Abiopeptide and Ferropeptide preparations in a dosage of 1.0 ml per 1 kg of live weight with the water. The drugs were given individually. At the end of the experiment, poultry were slaughtered for histological examination according to GOST R 33853-2010 «Poultry meat. Methods of histological and microscopic analysis». According to the research it was found that the use of drugs did not adversely affect the structure of the internal organs of the poultry. The liver morphology was not disturbed. The beam structure of the liver was preserved in the birds of all experimental groups. Hepatic lobules were of small size. The beams were short, consist of 1-2 rows of cells, located at a short distance from each other. The structure of the liver guinea fowl of the control group was broken. The overall morphofunctional state of the organs reffected moderately pronounced protein and fatty degeneration of hepatocytes, as well as acute arterial and venous hyperemia. According to the results of studies of muscle tissue, heart and spleen, the differences between the experimental and control groups were not established, the microstructure of tissues was within the physiological norm for this type of bird.