Theoretical investigations for the SF radical and its singly charged cation and anion, SF+ and SF-,have been performed on the MRCI/aug-cc-pVXZ (X =Q, 5, 6) levels of theory with Davidson correction.The process of extrapolating to the complete basis set (CBS) limit is adopted to remove the basis set truncation error.Both the core-valence correlation and the relativistic effect are considered in the computations.Geometrical parameters, potential energy curves, vibrational energy levels, spectroscopic constants as well as ionization potentials and electron affinities of the ground electronic state for all these species are obtained.The information with respect to molecular characteristics of the SFn (n=-1, 0, +1)systems derived in this work will be beneficial to extending our knowledge and to guiding further experimental or theoretical researches.