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As highly sensitive H₂S gas sensors, Au- and Ag-catalyzed SnO₂ thin films with morphology-controlled nanostructures were fabricated by using e-beam evaporation in combination with the glancing angle deposition (GAD) technique. After annealing at 500 °C for 40 h, the sensors showed a polycrystalline phase with a porous, tilted columnar nanostructure. The gas sensitivities (S = R_gas/R_air) of Au and Ag-catalyzed SnO₂ sensors fabricated by the GAD process were 0.009 and 0.015, respectively, under 5 ppm H₂S at 300 °C, and the 90% response time was approximately 5 s. These sensors showed excellent sensitivities compared with the SnO₂ thin film sensors that were deposited normally (glancing angle = 0°, S = 0.48).