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In this study, CdTe thin films were fabricated on soda-lime glass substrates via pulsed laser deposition and evaluated as immobilized semiconductor photocatalysts for the degradation of methylene blue under visible-light irradiation. XRD, AFM, SEM-EDS, photoluminescence, and photophysical characterization techniques were employed to elucidate the relationship between photocatalytic response and the structural, morphological, elemental, and optical characteristics of the fabricated thin films. Results show that increasing film thickness improves crystallinity, surface roughness, stoichiometry, optical absorption, and charge-carrier dynamics, while reducing the optical band gap from 1.71 to 1.37 eV. Among the fabricated samples, the 350 nm-thick CdTe film exhibited the highest photocatalytic performance, achieving 93.32% MB degradation after 220 minutes of visible-light irradiation, following pseudo-first-order kinetics with a rate constant of 0.0118 min⁻¹. Photocatalytic performance was strongly influenced by solution pH, with optimal degradation at pH 10. Furthermore, scavenger experiments demonstrated that reactive oxygen species, particularly superoxide radicals, played a dominant role in the overall degradation mechanism. These findings highlight CdTe thin films produced by PLD as promising immobilized photocatalysts for efficient wastewater treatment.