In this work the artificial magnetic shield structure was proposed aimed to improve the performance of preclinical volume coil for 7 Tesla MRI. Particularly, transmit efficiency as well as receive sensitivity of small-animal bird-cage coil was studied in the presence of both ideal electric and magnetic screen at the first step. Next, practical artificial magnetic shield structure using the principles of operation of high-impedance corrugated surfaces was suggested. B1+ distribution of the small-animal bird-cage coil equipped with corrugated surface structure was calculated and compared with the reference case of ideal electric screen. Numerical results demonstrated improved transmit efficiency and receive sensitivity of the bird-cage coil with the artificial magnetic shield structure comparing to the reference case.