Recently interest in alternative energy sources has increased throughout the world due to high oil price and environmental issues. Among alternative energy sources, hydrogen energy has been come into the spotlight in that it is sustainable and ideally pollution-free. In spite of its advantage as an alternative energy source, there are still some technological hurdles that should be overcome before hydrogen can be widely used. In particular, it is necessary to develop hydrogen sensing technology for safe hydrogen utilization. Optical hydrogen safety sensor based on gasochromic thin films, which is one of various hydrogen sensors, can detect the change of color of the film upon exposure to hydrogen gas in an area where hydrogen leak is suspected. For this application, sensitivity and durability of the sensor material is the most important factor. In this study, we have used Pt/Pd as a catalyst of the hydrogen sensor films. We found that it has improved sensitivity and durability over the usual Pd catalyst.