CdZn(S1-xSex)(2) thin films have been deposited onto glass substrates by the spray pyrolysis method at a 275 degrees C substrate temperature. The average optical transmittance of all the films was over 65% in the wavelength range 450-800 nm. The optical absorption studies reveal that the transition is direct with band gap energy values between 2.47-3.04 eV. The optical constants such as refractive index, extinction coefficient and dielectric constants have been calculated for these films. The dispersion parameters such as E-o (single-oscillator energy) and E-d (dispersive energy) have been discussed in terms of the Wemple-DiDomenico single-oscillator model. The values obtained by this method are suitable for many scientific studies and technological applications, such as gas sensors, heat mirrors, transparent electrodes, solar cells and piezoelectric devices.