Vehicle heater, comprising: - a heater housing, which is elongated in the direction of a housing longitudinal axis, with a housing circumferential wall defining a combustion air flow space in the radially outward direction, - a combustion chamber assembly unit, which is carried on the heater housing, with a combustion chamber receiving combustion air from the combustion airflow space, - a combustion air blower with a combustion air blower housing carried on the heater housing, wherein a combustion air inlet opening is provided in the combustion air blower housing for the inlet of combustion air into the combustion air blower, and - a combustion air connection unit, which is carried on the heater housing, with a combustion air passage duct, wherein the combustion air passage duct is open in the outward direction in a first duct opening area for receiving combustion air and the combustion air passage duct is open towards the combustion air inlet opening in a second duct opening area, wherein the combustion air connection unit has a plate-shaped connection unit body, wherein the connection unit body is positioned with a first body side located opposite an outer side of the housing circumferential wall and an outer side of the combustion air blower housing, characterized in that a sealing element is provided, which seals the combustion air blower housing in a gastight manner in relation to the heater housing, seals the combustion air blower housing in a gastight manner in relation to the combustion air connection unit and seals the heater housing in a gastight manner in relation to the combustion air connection unit. - a heater housing, which is elongated in the direction of a housing longitudinal axis, with a housing circumferential wall defining a combustion air flow space in the radially outward direction, - a combustion chamber assembly unit, which is carried on the heater housing, with a combustion chamber receiving combustion air from the combustion airflow space, - a combustion air blower with a combustion air blower housing carried on the heater housing, wherein a combustion air inlet opening is provided in the combustion air blower housing for the inlet of combustion air into the combustion air blower, and - a combustion air connection unit, which is carried on the heater housing, with a combustion air passage duct, wherein the combustion air passage duct is open in the outward direction in a first duct opening area for receiving combustion air and the combustion air passage duct is open towards the combustion air inlet opening in a second duct opening area, wherein the combustion air connection unit has a plate-shaped connection unit body, wherein the connection unit body is positioned with a first body side located opposite an outer side of the housing circumferential wall and an outer side of the combustion air blower housing, characterized in that a sealing element is provided, which seals the combustion air blower housing in a gastight manner in relation to the heater housing, seals the combustion air blower housing in a gastight manner in relation to the combustion air connection unit and seals the heater housing in a gastight manner in relation to the combustion air connection unit.