Abstract Chemiresistors based on graphene/SnO2 quantum dots composites have been fabricated for low temperature detection of liquefied petroleum gas (LPG). Because of the flammable nature of LPG, this investigation focused on the detection of LPG at low temperatures, in order to find a cost-effective and low risk detection method. The structural, morphological, and optical characterization of synthesized composites was done using X-ray diffraction, field emission-scanning electron microscopy, transmission electron microscopy, UV-visible and fluorescence spectroscopy. The as-obtained composites show significantly better performance for the detection of LPG. The sensing mechanism used defects chemistry.