The embodiments of the present disclosure provide methods and Internet of Things (IoT) systems for managing a smart gas safety hazard item based on a Geographic Information System (GIS). The method includes: obtaining gas safety hazard data of a gas pipeline network; dividing the gas pipeline network into one or more gas inspection units based on the gas safety hazard data and geographic information data of the gas pipeline network; assigning one or more gas safety hazard items to the gas inspection unit based on the gas safety hazard data corresponding to the gas inspection unit; determining a processing plan of the gas inspection unit; and determining an inspection plan based on the processing plan and a gas GIS.