Polymer metal oxide nanocomposite (PMON) material is synthesized by the chemical oxidative polymerization. The synthesized nanocomposite is characterized by the Field Emission Scanning Electron Microscope (FESEM), X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). The FESEM images of the PANI (polyaniline) shows the formation of nanofibers of length 200 nm and diameter 50 nm. The FESEM micrograph composite shows that polyaniline is encapsulating the TiO2-Al3+ nanomaterials. The average size of the encapsulation is found to be 300 nm in diameter. The well defined peaks in the XRD spectra confirm the crystalline structure of TiO2-Al3+. Our sensor is able to detect up to 5 ppm concentration of ammonia gas. The sensor is stable up to 100 days and works at room temperature. The slight shift of base line is seen. The sensor is recovered automatically without flushing nitrogen gas. The sensor has the sensitivity of 1.0913 ppm-1.