In this work, SnO2 porous nanosolids were obtained from SnO2 nanopowders by using a solvo-thermal hot-press method. Then, by using the conventional thick-film sensors preparation technology, SnO2 porous thick-film gas sensor was prepared from it. Meanwhile, polyaniline (PANI) was synthesized by chemical oxidation polymerization. After that, by mechanical method, the SnO2/PANI composite gas sensors were fabricated. The intrinsic resistances and gas sensing properties of sensors to NO2, NH3, H2 and ethanol vapor were tested. Compared with the SnO2 porous gas sensors, the optimum operation temperature of SnO2/PANI hybrid gas sensors decreased dramatically. And SnO2/PANI hybrid gas sensors showed satisfying selectivity and high sensitivity for NO2.