The present contribution reports on the electronic structure and optical properties of the polyaniline polymer material. The calculations are performed using ab initio total energy calculations within the full-potential linearized augmented plane wave method in the framework of the density functional theory. The generalized gradient approximation is used to treat the effects of exchange and correlation. The fundamental band-gap energy and static and high-frequency dielectric constants of the polymer of interest are predicted. The optical spectra against the photon incident energy along both the x- and z-axis are presented and examined.