An experimental morphological study in 56 animals has been performed in order to analyze the effect of cerebrolysin on the dynamics and long-term results of peripheral nerve regeneration after the transection and microsurgical suturing depending on the scheme of the preparation of paraneural infusion. The regeneration process was evaluated after 2.5; 4; 6 and 12 months. There was a stimulating effect of the preparation on the regenerative growth and differentiation of nerve fiber axial cylinders, vascularization of the distal segment of regenerating nerve and the trophic condition of myelin-forming Schwann cells. When the preparation is used according to the prolonged scheme, the effect persists for up to 10.5 months after the end of paraneural injection course.