Control of the in-plane crystallographic orientation of YBa2Cu3O7-x (YBCO) films on (100) MgO substrates is of significant application value due to the selective enhancement of superconducting properties. In the present work, the preparation, crystallographic and superconducting properties of YBCO films deposited on MgO substrates are reported. Crystallographic in-plane orientation was realized by means of tailoring the pulsed laser deposition conditions and the use of interfacial buffering structures. Superconductiong properties were measured for films having different in-plane orienations. The results indicate that the 0 degrees in-plane oriented films showed the highest current density of 1.62 MA/cm(2) that was attributed to the elimination of high-angle grain boudaries. Additionally, the growth mechanism of YBCO films was discussed in terms of crystallographic and thermodynamic theory. (c) 2012 Elsevier B.V. All rights reserved.