The　impacts　of　three　charged-residue-involved　mutations,　E46A,　R3E,　and　R3E/L66E,　on　the　thermostability　and　folding　behavior　of　the　cold　shock　protein　from　the　themophile　Bacillus　caldolyticus　(Bc-Csp)　were　investigated　by　using　a　modified　Go-like　model,　in　which　the　nonspecific　electrostatic　interactions　of　charged　residues　were　taken　into　account.　Our　simulation　results　show　that　the　wild-type　Bc-Csp　and　its　three　mutants　are　all　two-sate　folders,　which　is　consistent　with　the　experimental　observations.　It　is　found　that　these　three　mutations　all　lead　to　a　decrease　of　protein　thermodynamical　stability,　and　the　effect　of　R3E　mutation　is　the　strongest.　The　lower　stability　of　these　three　mutants　is　due　to　the　increase　of　the　enthalpy　of　the　folded　state　and　the　entropy　of　the　unfolded　state.　Using　this　model,　we　also　studied　the　folding　kinetics　and　the　folding/unfolding　pathway　of　the　wild-type　Bc-Csp　as　well　as　its　three　mutants　and　then　discussed　the　effects　of　electrostatic　interactions　on　the　folding　kinetics.　The　results　indicate　that　the　substitutions　at　positions　3　and　46　largely　decrease　the　folding　kinetics,　whereas　the　mutation　of　residue　66　only　slightly　decreases　the　folding　rate.　This　result　agrees　well　with　the　experimental　observations.　It　is　also　found　that　these　mutations　have　little　effects　on　the　folding　transition　state　and　the　folding　pathway,　in　which　the　N-terminal　beta　sheet　folds　earlier　than　the　C-terminal　region.　We　also　investigated　the　detailed　unfolding　pathway　and　found　that　it　is　really　the　reverse　of　the　folding　pathway,　providing　the　validity　of　our　simulation　results.