The influence of the cattle cord blood low-molecular fraction (CBF below 5 kDa) as part of the rehabilitating medium in comparison with Actovegin on the functional activity of neutrophils after cryopreservation was studied. Incubation of frozen-thawed neutrophils in the rehabilitating media containing the low-molecular fraction or Actovegin stimulates their phagocytic function, in particular engulfing and digesting ability. After incubation of frozen-thawed neutrophils in the media containing 0.15 mg per ml CBF or 1.5 mg per ml Actovegin, their oxygen-dependent metabolism was activated, since the number of NBT-positive neutrophils increased significantly in comparison with the control. Gel-penetrating chromatography of CBF and Actovegin revealed differences between their chromatograms reflecting differences between the compositions compared. The recovery of the functional activity of frozen-thawed neutrophils was possible in the media containing the cattle cord blood low-molecular fraction (below 5 kDa) or Actovegin at 0.15 mg per ml and 1.5 mg per ml, respectively.