We report the successful synthesis of superconducting YBa2Cu3O7−&dgr;(YBCO) (100) thin films with alignment of the in‐planecaxis. These films were grown on single crystal NdGaO3(110) substrates. The twofold symmetry of the substrate surface is believed to lead to anisotropic alignment of the in‐planecaxis of the epitaxial YBCO (100) film. X‐ray diffraction studies indicate that over 80% of the film grew epitaxially with the YBCO [100] perpendicular to the substrate surface, and YBCO [001] aligned along one pseudo‐cubic axis of the NdGaO3. The superconductivity onset of the film was measured to be 89 K by ac susceptibility.