Hydrogenation effects on electrical properties of n-type and undoped InGaP epi layers lattice matched to GaAs was investigated. It was found that the hydrogenation under a proper condition can be resulted in a Auh-InGaP Schottky diode with a good rectifying characteristics as well as an effective defect passivation. These improvement were thought to be resulted from the atomic hydrogen diffused into InCaP neutralized Si donor and passivated recombination centers near the surface.