The complete active space self-consist field method followed by the internally contracted multireference configuration interaction method has been used to compute the potential energy curves of $X^2prod_g$, $a^4prod_u$, $A^2prod_u$, $b^4sum_{g}^{-}$, and $B^2sum_{g}^{-}$ states of $S{_2}^+$ cation with large correlation-consistent basis sets. Utilizing the potential energy curves computed with different basis sets, the spectroscopic parameters of these states were evaluated. Finally, the transition dipole moment and the Franck-Condon factors of the transition from $A^2prod_u$ to $X^2prod_g$ were evaluated. The radiative lifetime of $A^2prod_u$ is calculated to be 887 ns, which is in good agreement with experimental value of $805{pm}10$ ns.