Based　on　proposed　analytical　model　describing　the　thermodynamic　functions　of　nanograin　boundaries,　the　thermodynamic　features　of　nanograin　boundaries　were　introduced　into　the　Cellular　Automaton　algorithm.　With　the　hybrid　model,　the　quantitative　and　visual　simulations　of　nanograin　growth　have　been　carried　out.　The　simulation　results　show　that　the　nanograin　growth　kinetics　is　different　from　the　normal　grain　growth　kinetics　in　conventional　polycrystalline　materials.　The　nanograin　growth　exponent　(n)　is　not　a　constant　as　in　the　polycrystalline　metals　which　equals　2,　but　changes　with　the　growing　process,　which　has　a　range　of　1.70-6.59.　The　excess　free　energy　of　the　nanograin　boundaries　is　the　driving　force　for　nanograin　growth,　which　is　closely　related　with　the　grain　size.　The　thermodynamic　features　of　nanograin　boundaries　strongly　affect　the　energy　state　of　the　nanocrystalline　materials　hence　the　nanograin　growth　kinetics,　as　a　result　of　the　nanoscale　effect.　For　the　simulations　of　nanograin　growth　the　thermodynamic　features　of　nanocrystalline　materials　should　be　introduced.