The invention relates to a furnace with a chimney provided with a heat dissipation section. The furnace comprises a furnace body, wherein the furnace body is provided with the chimney, an air inlet and a gas fuel inlet, the chimney is provided with the heat dissipation section, the heat dissipation section is a rectangular pipe defined by a left wall, a front wall, a right wall and a rear wall, the heat dissipation section is internally provided with a plurality of aluminum plates extending in the extending direction of the heat dissipation pipe, the aluminum plates are connected with the inner surface of the heat dissipation section, a heat dissipation plate is arranged on the surface of at least one side of the heat dissipation section, the heat dissipation plates extend in the directionperpendicular to the axis of the heat dissipation section, the heat dissipation plates are distributed in the axial direction of the heat dissipation section, the heat dissipation plates comprise outer plates with one ends connected to the heat dissipation pipe, middle plates with one ends capable of penetrating through the other ends of the outer plates in a telescopic mode, and inner plates with one ends capable of penetrating through the other ends of the middle plates in a telescopic mode. The furnace aims to achieve the effects that the heat dissipation effect on tail gas can be adjusted, and the problem that the heat dissipation effect on the tail gas of an existing fuel furnace cannot be adjusted is solved.