As‐grown superconducting YBa2Cu3O7−ythin films with various thicknesses were successfully grown on lattice‐matched NdGaO3substrates by ArF laser ablation deposition. An as‐grown 2000‐A˚‐thick film has a zero‐resistance temperature (Tc) at 90 K and a 170‐A˚‐thick film has aTcat 88 K. The existence of a thin interfacial diffusion layer between a 170‐A˚‐thick film and the substrate was observed by Auger electron spectroscopy. Rutherford backscattering spectroscopy suggest that as‐grown YBa2Cu3O7−yfilms on NdGaO3substrates are high‐quality crystals. It is demonstrated that the NdGaO3has considerable potential as an electronic substrate material by less interfacial diffusion layer and good crystallinity of grown thin films.