The invention provides a combustion device for domestic solid waste treatment through a large coal combustion boiler and further provides a combustion method for the domestic solid waste treatment through the large coal combustion boiler. The combustion device comprises the coal combustion boiler and a solid waste combustion assembly, a hearth of the coal combustion boiler is provided with a primary and secondary air nozzle set, an over fire air nozzle set and a solid waste inlet, and the solid waste combustion assembly comprises a feed hopper. The feed hopper is downwards connected with the top of a feed pipe, and the bottom of the feed pipe is bent, then connected with the outer side of the solid waste inlet and connected with a water cooling bed extending into the hearth from the solidwaste inlet. The side, away from the wall of the hearth, of the feed pipe is subjected to hole forming and connected with a material stirring air pipeline and a material pushing mechanism. The tail ofthe coal combustion boiler is provided with a smoke gas recycling device for extracting recycled smoke gas to serve as material stirring air to be sprayed into the material stirring air pipeline. According to the combustion device and method for the domestic solid waste treatment through the large coal combustion boiler, expensive combustible combustion-support fuel does not need to be input, andthus the operation cost is reduced; harmful substances such as dioxin can be resolved, and environment pollution caused by waste incineration is reduced; and the combustion device is simple in structure, convenient to operate and reliable in performance.