Abstract: The distribution of protium and deuterium in zirconium hydride films are analyzed by using depth profiles and images of SIMS. The results show that protium and deuterium are uniform in the hydride films, but they are degressive in the transition layers and disappear at the boundary between the layers and substrates. The concentration of protium is higher than that of deuterium in zirconium hydride films because of the isotope effects when they are hydrogenated in the atmosphere of n(H):n(D)= 1.20:1. Contaminations of Alt Fe, K and Na on the surface could result in a different distribution of H and D at the surface of zirconium films. Non-uniform distributions of D and H is directly correlated with Al and Zr, respectively.