Recent pressure vessel surveillance reports contain DPA rates as an exposure parameter. In order to assess the reliability of the DPA data, it is useful to inter-compare available DPA data processed from current evaluated nuclear data libraries. We generated the damage energy production cross sections for elements in a RPV of a PWR and a core barrel of a LMR, with NJOY 97 code system from the currently available evaluated nuclear data libraries, ENDF/B-VI.5, JEF-2.2, JENDL-3.2, BROND-2.2, and CENDL-2.1. The DPA rates using the neutron spectra from the surveillance test of Korean PWR Ulchin Unit 1 and the design of KALIMER LMR were inter-compared. The results show a maximum relative difference of 22% for carbon steel in a PWR. The effect of partial damage cross sections such as elastic scattering, inelastic scattering and disappearance reaction has been analyzed as well as status of iron, chrome and nickel.