The 15N+ 1H→12C+4He+4.43MeV(γ-ray) nuclear resonance reaction has been used to study the H concentration versus depth in Pd. It is a precise method because. (1) it has a high depth resolution (～50?); (2) γ-ray can be detected easily after penetrating low temperature and vacuum systems; (3)the isolated resonance has an energy of 6.385 -MeV with very narrow width (6-keV); (4) it has reaction cross section of 0.46 barn and high sensitivity. In this paper, the principle of the method, the experimental set-ups as well as hydrogen distribution in the superconducting Pd (H) prepared at different conditions are discussed. In comparison with the observations on the presure charged sample, some new ideas about the hydrogen behavior in this kind of superconductor are given.