Optoelectronic and magnetic properties for Sn(O1-xNx)2 material were examined using quantum chemical ab initio calculation software WIEN2K based on the first principles of density functional theory. The density of states, the band structure, the magnetism, dielectric function and the refractive index are analyzed. The results show that the band gap frist narrowed and then increases with the increase of doping concentration of nitrogen substituting oxygen, the band gap of Sn(O1-xNx)2 becomes the narrowest when the concentration of nitrogen is 12.50%. As a result of the contribution of the electron of N 2p orbit, a low acceptor level appears in a range of 0.551.05 eV, and the level spliting and the orbit overlap appear in the valence band and conduction band. The SnO bond is stronger than the NO bond. From the magnetism, the magnetic moment is determined by N atoms. We know that the optical absorption edge is widened from the imaginary part of dielectric function. The main transition peak is red shifted and the refractive index is corresponding to the dielectric function related to the transition of electrons.