In　order　to　solve　a　practical　NP　problem　of　map　four-coloring　by　using　DNA　parallel　algorithm,　a　concept　of　DNA-chip-group　technology　is　proposed,　which　is　based　on　advanced　DNA　computing　theorem,　DNA-chip　technology　and　database　technology.　The　operation　steps　of　the　DNA-chip-technology　are　introduced　through　solving　a　four-coloring　problem　of　a　maximal　planer　graph-map　of　China,　which　includes　the　outside　part　of　the　boundary　as　well　as　the　inside　ones.　The　computer　simulation　of　the　biochemical　experiment,　the　analysis　and　processing　on　the　database　is　carried　out,　and　all　of　the　correct　coloring　schemes　are　obtained.　The　powerful　capability　of　application　of　the　DNA-chip-group　technology　in　solving　NP　problem　is　proved.