The study of the effect of chitosan succinate use on the hematological indicators of dairy cows is relevant. It has been established that there was a clear tendency to increase in the number of white blood cells by 10.12% in animals of group 3 (P < 0.1) on the 10th day of the experiment in cows receiving low-molecular-weight chitosan succinate, in the second group the increase in this indicator by 2.94% was unreliable. On the 20th day of the experiment, an intensive increase in the number of white blood cells was observed in animals of both experimental groups by 14.63–17.38% (P≤0.01), respectively, for the experimental groups of cows. On the 10th day on the background of the use of low-molecular-weight chitosan (group 3), a significant decrease in the number of red blood cells was found, compared with the background, by 8.34% (P≤0.05). On the 20th day, the decrease in the number of red blood cells was already significant in both experimental groups, and their level was 6.09±0.33...6.38±0.20·109/l (P≤0.05), respectively. On the 60th day of the study, this trend was maintained only in group 3, and the concentration of red blood cells was lower by 12.64 (P < 0.05) compared to the initial values. By the 60th day, there was an increase in the level of hemoglobin index up to 126.12±9.10 g/l.