Comprehensive　ab　initio　calculations　were　performed　on　the　coordination　of　Pt(II),　Pd(II)　and　Ni(II)　adducts　to　the　N(7)　of　guanine　and　guanine-cytosine　(GC)　base　pair　at　the　DFT　level.　The　fully　optimized　geometries　of　the　metal　complexes　were　obtained　and　the　stabilization　energies　of　the　interaction　between　metal　adducts　and　nucleobase　were　calculated　with　B3LYP　method　by　using　6-31*　basis　set　for　the　light　atom.　While　the　effective　core　potential　(ECP)　is　used　for　metal　cation.　The　results　show　that　both　cispalladium　and　cisnickel　cause　similar　geometric　changes　of　the　base　pair　as　cisplatin.　For　the　coordination　of　metal　adducts　to　guanine,　platinum　adduct　possesses　the　highest　stabilization　energy;　but　the　interaction　between　metal-guanine　and　cytosine　for　nickel　is　larger　than　that　for　platinum　and　palladium.　It　is　worthy　to　note　that　hydrolysis　effect　can　also　cause　significant　changes　in　H-bonds.