A new ternary conducting polymer composite of polypyrrole (PPy), prussian blue (PB), titanium dioxide (TiO2), PPy-PB-TiO2 synthesized by in-situ oxidative polymerization is reported for fiber optic gas sensing applications. The phase, morphology, optical and thermal studies of the polymer composite are analyzed using various analytical techniques. The gas sensing properties of the clad-modified PPy-PB-TiO2 sensor are investigated upon exposure to different volatile gas analytes of varying concentrations (0−500 ppm) at room temperature. The experimental results of PPy-PB-TiO2 sensor exhibits high sensitivity and selectivity to ammonia than acetone and ethanol; the sensing characteristics outstripped that of pure TiO2 and PPy-PB sensors. Thus, the present work demonstrates clad removed PPy-PB-TiO2 sensor as an excellent candidate for fiber optic gas sensing application. © 2021 Elsevier GmbH