An exhaust heating apparatus comprising: a housing def ining a firing chamber, the housing being jointed to an exhaust pipe defining an exhaust passage, the exhaust pipe being connectable between an internal combustion engine and an exhaust emission purifier; a fuel supply valve for injecting fuel into the firing chamber communicating with the exhaust passage through a junction port formed on a wall of the exhaust pipe; and ignition means including a heat generating portion for igniting the fuel injected into the firing chamber, the heat generating portion of the ignition means being arranged in the vicinity of the downstream wall surface (27 D) in the housing, wherein a part of the exhaust gas flowing in the exhaust passage flows from the junction port into the firing chamber so that ignition of a mixture of exhaust gas and fuel injected into the firing chamber generates a combustion gas that flows out from the junction port to the exhaust passage together with exhaust gas newly flowing into the firing chamber, and an angle (θ 1) between a wall surface in the exhaust pipe positioned upstream of the junction port in the exhaust passage and adjacent to the junction port, and an upstream wall surface (27 U) in the housing positioned upstream of the exhaust passage, is set to an obtuse angle, and an angle (θ 2) between a wall surface in the exhaust pipe positioned downstream of the junction port in the exhaust passage and adjacent to the junction port, and a downstream wall surface (27 D) in the housing positioned downstream of the exhaust passage, is set to an obtuse angle, and characterized in that a posture of the fuel supply valve is set to the downstream wall surface (27 D) in the housing such that the fuel injected from the fuel supply valve collides with the downstream wall surface (27 D) in the housing and splashes toward the exhaust passage through the junction port. a housing def ining a firing chamber, the housing being jointed to an exhaust pipe defining an exhaust passage, the exhaust pipe being connectable between an internal combustion engine and an exhaust emission purifier; a fuel supply valve for injecting fuel into the firing chamber communicating with the exhaust passage through a junction port formed on a wall of the exhaust pipe; and ignition means including a heat generating portion for igniting the fuel injected into the firing chamber, the heat generating portion of the ignition means being arranged in the vicinity of the downstream wall surface (27 D) in the housing, wherein a part of the exhaust gas flowing in the exhaust passage flows from the junction port into the firing chamber so that ignition of a mixture of exhaust gas and fuel injected into the firing chamber generates a combustion gas that flows out from the junction port to the exhaust passage together with exhaust gas newly flowing into the firing chamber, and an angle (θ 1) between a wall surface in the exhaust pipe positioned upstream of the junction port in the exhaust passage and adjacent to the junction port, and an upstream wall surface (27 U) in the housing positioned upstream of the exhaust passage, is set to an obtuse angle, and an angle (θ 2) between a wall surface in the exhaust pipe positioned downstream of the junction port in the exhaust passage and adjacent to the junction port, and a downstream wall surface (27 D) in the housing positioned downstream of the exhaust passage, is set to an obtuse angle, and characterized in that a posture of the fuel supply valve is set to the downstream wall surface (27 D) in the housing such that the fuel injected from the fuel supply valve collides with the downstream wall surface (27 D) in the housing and splashes toward the exhaust passage through the junction port.