This study investigated the effect of tungsten oxide (WO₃) doping on the optical properties of yttrium oxide (Y₂O₃) thin films prepared by pulsed laser deposition (PLD). Films containing 0, 3, 6, and 9 wt% WO₃ were annealed at 600 °C for 2 h. UV–Visible spectroscopy revealed increased absorbance and decreased transmittance with increasing WO₃ concentration. The optical band gap changed from 2.480 eV for the undoped film to 2.504, 2.172, and 2.138 eV for films containing 3, 6, and 9 wt% WO₃, respectively. These changes suggest that WO₃ incorporation modifies the electronic structure of Y₂O₃ and may introduce localized energy states that enhance light absorption. The results highlight the potential of WO₃-doped Y₂O₃ thin films for optoelectronic applications, particularly solar energy conversion and optical sensing.