Abstract. The study aimed at evaluation of the effect of colostral supplement on humoral immunity, growth and health state of calves until the 3rd month of life. Examinations were carried out on 40 Polish Black-and-White Holstein-Friesian calves. After birth, the calves were separated into two groups (20 calves each): control group – without addition of colostral supplement, and experimental one – with colostral supplement in diet. Blood was sampled from each calf on day 5 and 30 of life, and total protein, albumin, and alpha, beta and gamma globulin levels were determined in it. Evaluation of calves’ growth and development course was carried out basing on weighing and daily gain results. The favourable effect of colostral supplement on calves’ health state and body weight gains was found. No significant effect of colostral supplement on total protein level or gamma-globulin fraction level was found. The effect of colostral supplement on reduction of alpha-globulin fraction decrease was found in a time period until the 30th day of calves’ life (P≤0.01). The study so far point to the purposefulness of using this supplement, in particular in the case of colostrum deficiency or its poor quality.