Abstract: A relational ENDF library software was designed. It provides both specialised and non-specialised users with an easy and efficient access to the following nuclear databases: five neutron evaluated libraries(BROND, CENDL, ENDF, JEF, JENDL), IAEA photonuclear library and the charged particle data of FENDL library. This software includes one nuclear data display program and also can easily reconstruct nuclear data in original standardized formats from the relational databases. Users are allowed to make online plots and over-plots for the evaluated cross section data retrieved from different built-in nuclear databases.