This work presents the fabrication and characterization of a novel hydrogen-detecting micro-resonator based on the expansion of palladium (Pd) as it is exposed to hydrogen (H2) gas. The working principle of the device has been confirmed and it shows a stronger response at a given H2 partial pressure than what theory predicts using bulk Pd material parameters. This may be explained by properties that are specific for Pd thin films in the nanometre range. The results suggest that the presence of very dilute amounts of hydrogen gas could be detected and the dynamic range of the device could be greatly increased if the device is optimized further.