The invention provides a sealing device and a coal charger. The sealing device is applied to the coal charger. The sealing device comprises a base, wherein one side of the base is connected with one end of at least one resetting part and the other side of the base is connected with a flange of a guide sleeve of the coal charger; a knife edge sealing part, wherein one side of the knife edge sealing part is connected with one end of the at least one resetting part, and the cross section of the knife edge sealing part is of a door-like structure; and a sealing membrane which wraps the outer sides of the base and the knife edge sealing part and is used for sealing a gap between the base and the knife edge sealing part. Thus, good sealing effect is obtained between the knife edge sealing part and the upper horizontal plane, full of uneven pouring materials, of a furnace seat; the resetting part can provide sufficient pressure in extremely narrow space, so air tightness between the knife edge sealing part and the furnace seat is further guaranteed; thus, air tightness between the coal charger and the furnace seat can be guaranteed in the case of deformation of the furnace seat, overflowing of flue dust can be prevented, and environmental pollution is avoided.