A Cu tetraphenylporphyrin (CuTPP) gas sensor has been designed and fabricated for detection of volatile organic compounds (VOCs). The synthesized CuTPP was characterized by X-ray photoelectron spectroscopy (XPS) and nuclear magnetic resonance spectroscopy (1H NMR), then deposited onto a single mode potassium (K+) ion-exchanged glass optical waveguide (OWG) surface by spin coating and dip-coating of a CuTPP thin film on the surface of an alumina ceramic tube, where they acted as a sensing layer. The surface topography of the CuTPP thin film/K+-exchanged layer was investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM), where it showed a root-mean-square (RMS) roughness of about 3.4 nm with cross-section of nanoparticles exhibit rectangular pyramid morphology. CuTPP film sensors used to detect styrene gas as a typical example of VOCs. The experimental results showed that, at room temperature, CuTPP thin film/K+-exchanged OWG sensing device revealed higher response to styrene and xylene in the range of 10 ppb-1000 ppm; the response to CuTPP electro-chemical sensor response to styrene and xylene were 3.6 and 2.3, respectively.