3D printed scaffold represents a promising approach for treatment of spinal cord injury (SCI). Here we suggest an innovative biotechnological approach for free-form 3D printing of scaffolds with a biomimetic architecture at a spatial resolution up to a micrometer, which were used for implantation in treatment of SCI in one-month-old Wistar rats. The approach is based on 2-photon photopolymerization of organic polymers and is scalable to lesion geometries. The scaffolds were implemented as multiple densely packed parallel micro-tunnels (~50 μm) running through their whole length. Having thin walls (~5 μm) between tunnels, the scaffolds are almost hollow and simultaneously creates a large internal surface area, providing thereby a natural spatially oriented substrate for the axonal and vascular ingrowth. We have found that the scaffolds, implanted in the excision of the lateral half-fragment of the spinal cord at the level of T12–T13, were well integrated into the spinal cord without the formation of a significant gliofibrous scar. Axons surrounded by oligodendrocytes, as well as vessels were observed in almost each tunnel. Implantation also significantly improved the motor and sensory functions of the paretic ipsilateral limb by 4th week, and the achieved recovery was maintained until the end of 5th month after the operation. Thus, 3D oriented hollow scaffolds having a large internal surface area creates conditions for enhancing spinal cord regeneration and recovery of the motor and sensory function of the paretic limb. Supported by NRFU grant # 2021.01/0328