The invention discloses a gasification combustion coupling method and a gasification combustion coupling system for dual fluidized bed solid fuel. The method comprises the following steps of: (1) performing a pyrolytic gasification reaction of the sold fuel and a gasification agent for fluidifying and reacting in a bubbling bed gasification reactor to generate gas and solid carbocoal which is not subjected to the pyrolytic gasification reaction completely, wherein heat required by the pyrolytic gasification reaction is mainly supplied by a circulating heat carrier; (2) conveying the solid carbocoal and the circulating heat carrier into a circulating fluidized bed boiler, and combusting the solid carbocoal in the circulating fluidized bed boiler to heat the circulating heat carrier and generate high-temperature flue gas; (3) conveying the flue gas and the heated circulating heat carrier into a flue gas separation device, so that the circulating heat carrier is separated from the flue gas; (4) conveying the circulating heat carrier separated from the flue gas into the bubbling bed gasification reactor to supply the heat to the pyrolytic gasification reaction. In the method, the continuous and stable running of the gasification combustion coupling process is realized by combining the conventional water gas (or semi-water gas) intermittent production process.