A hydrogen sulfide gas-sensitive chemiresistive sensor was screen printed on a flexible polyethylene terphthalate substrate using a nanocomposite of polyaniline(PANI)/WO₃/CuCl₂ (PET). FE-SEM analysis validated the nanoscale morphology of the composite, which revealed tungsten oxide particles in nano-rectangular forms, i.e., rod-like structures. The gas-sensing capabilities of the film were affected by the PANI and WO₃ ratio, with the optimal ratio of 0.5 showing the best response. It was tested at various H₂S gas concentrations and demonstrated a progressive response as the gas concentration increased. PANI/WO₃/CuCl₂ film was more sensitive than PANI/CuCl₂ binary composite film. Around 1 ppm of gas concentration, with a response time of 67.9 s at room temperature, the highest response of two orders of magnitude change was observed, of 93%. This study found that PANI/WO₃/CuCl₂ is an excellent composite for improving the reversibility and humidity sensitivity of PANI/CuCl₂ composite-based chemiresistors during H₂S gas sensing, and that screen printing is a simple and cost-effective method for producing stable and uniform film-based chemiresistive gas sensors.