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In this study, tin dioxide nano-particles with Graphite by spray pyrolysis method coated on the glass as a humidity sensor for first time. The sensor fabricated with mixing tin tetra chloride solution and graphite dispersed in ethanol used as a spray solution. The spray solution sprayed on heated glass at 300, 400, and 450 C. A digital ohmmeter recorded the sensor response at different humidity level and headspace standard saturated salt solutions used for fabrication of different humidity level. The surface characterizations of the sensor studied by atomic force microscope AFM and scanning electron microscope SEM. The sensitivity of the sensor demonstrated at different pyrolysis temperature. The effect the thickness on sensitivity and response-recovery time studied. Study on sensor show the sensor has good sensitivity at room temperature, excellent recyclability, and durability to humidity. The sensor with different operation mechanism has selective behavior to humidity.