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SnO2 nanomaterial was synthesized by a simple one-step hydrothermal method and the structure and morphology of the material was characterized by XRD, SEM, TEM and nitrogen adsorption-desorption. The results showed that the prepared SnO2 nanomaterial was composed of hollow nanospheres with a diameter of 150-200 nm and had a large specific surface area (82.6 m2/g). The SnO2 gas sensitive paste was applied to the interdigital electrode by screen printing technology to form thick film gas sensing elements, and the gas sensing properties of the elements toward hydrogen were studied. The results showed that SnO2 hollow nanospheres had high response value and fast response speed to hydrogen ranging from 5 to 200 ppm at a low temperature (200 oC). This is attributed to the hollow structure and large specific surface area of the prepared SnO2 material, which facilitates the adsorption and diffusion of hydrogen gas.