The present investigation deals with the fabrication of H2S gas sensor based on semiconducting oxide,TiO2. Among the various metal oxide additives tested, Al2O3 is outstanding in promoting the sensing properties of nanosized TiO2 based H2S gas sensor. XRD pattern of TiO2 /Al2O3 shows complete phase formation with anatase structure and grain growth 45 nm. The TiO2 sensor loaded with 5 wt% Al2O3 and 0.5 wt% Pd shows increase in sensitivity to H2S. The cross sensitivity of 0.5 wt% Pd:5 wt% Al2O3 doped TiO2 also checked for CO, LPG and H-2 gases. The highest sensitivity for low concentration of H2S was observed using TiO2 based mixed Al2O3 and Pd. The H2S sensor shows high sensitivity and undesirable cross sensitivity effect using TiO2/Al2O3/Pd as sensing materials.