The invention discloses a residual heat recycling and dust removal integrated coal-fired boiler with a conveniently detachable draught fan. A cyclone dust removal residual heat efficiency recycling device is formed by overlapping a tubular heat exchanger and a cyclone dust remover; a boiler exhaust pipe is connected with the cyclone dust remover in a tangential direction; after cyclone dust removal is carried out, ash is discharged from a cone bottom through an air closing device; exhaust is connected with a cone body through a rotational flow ascending pipe, is uniformly dispersed and then penetrates through tubes; after being concentrated through an upper conical hopper, the exhaust is discharged by the draught fan through an exhausting pipe; a high-level water tank is connected with the lower part of a shell side of the tubular heat exchanger; and an impeller of the draught fan can be used for cleaning the ash in real time through a centrifugal force. The residual heat recycling and dust removal integrated coal-fired boiler realizes integrated type residual heat recycling and dust removal; more importantly, a dismounting technology of the draught fan is greatly improved, and pressure on the end face of a screw shaft shoulder of a screw cap part can be simply eliminated in a dismounting process, so that the problem that thread assembling of the draught fan is continuously automatically locked under the action of a load and thus detachment is not easy is effectively solved; and therefore, the technical scheme is particularly suitable for conveniently detaching a large-size draught fan locked through a thread and the effect is particularly remarkable.