La2O3 thin films were synthesized by spray pyrolysis method and this deposited thin films characterized using structural and morphological characterization techniques. The electrochemical properties such as cyclic voltammetry, galvanostatic charge-discharge, EIS were studied. The symmetric device based on La2o3 thin film electrode was fabricated and its performance also studied. The gas sensing properties of La2o3 thin films were measured at various temperature, the concentration of gasses. Also, the selectivity and stability study of La2o3 thin films were checked.