The electronic absorption spectra of disperse red 19 (DR19) dye were used to calculate non-linear optical properties (NLO) and intramolecular charge transfer (ICT) characteristics in four different polarity solvents. DR19 dye shows good NLO responses with high values of NLO parameters (αCT = 1.65 × 10-23 e.s.u., βCT = 57.60 × 10-29 e.s.u. and γCT = 0.16 × 10-32 e.s.u.), in methanol medium. Then, using the NLO parameters the generalized Mulliken-Hush analysis was performed in order to evaluate the ICT characteristics responsible for the nonlinear optic character of this azo disperse red dye. The previous findings (J. Phys. Chem. A 18 (1997) 3222-3226, Song et al. [1]) and results from the present study indicate that DR19 dye is a material showing good NLO properties and that find applications in various fields.