In0.95Mn0.05Se films with of thickness 750 nm were evaporated by using thermal evaporation technique, this film was irradiated by γ radiation with doses (0,40 and 120 KGy). Both of dispersion energy (Ed) and oscillating energy (Eo) were determined. The values of lattice dielectric constant (εL) and free carrier concentration/effective mass) (N/m*) were calculated. On the other hand, the values of first order of moment (M-1), the third order of moment (M-3) and static refractive index (no), were determined. Both of dielectric loss (ε\) and dielectric tangent loss (ε\\) for these films increased with photon energy (hν). Also, the same behavior was noticed for the real part of optical conductivity (σ1) and imaginary part of optical conductivity (σ2). The Linear optical susceptibility (χ(1)) increases with (hν)for all compositions. The nonlinear optical parameters such as, nonlinear refractive index (n2), the third-order nonlinear optical susceptibility (χ(3)), non-linear absorption coefficient (βc) , were determined theoretically. Both of the electrical susceptibility (χe) and relative permittivity (εr) increase with photon energy and had a highest value near the energy gap. The semiconducting results such as, density of the valence band, conduction band and Fermi level position (Ef) were calculated.