A glow plug with a pressure sensor comprising: a housing in a cylindrical shape that is extended in a direction of an axis line; a heater unit in a rod shape that has a rear end part placed in the housing and a front end part protruded from a front end of the housing and is movable along the direction of the axis line; a coupling member in a thin film shape that enables the heater unit to move along the direction of the axis line and couples the heater unit with the housing; and a pressure sensor that detects a pressure based on a load transmitted via the heater unit, wherein the coupling member includes a second cylinder section and a joint section; the glow plug being characterised in that: the coupling member includes a first cylinder section that is formed in a tubular shape along the axis line; an edge portion of the coupling member and the heater unit are joined together by laser welding performed from a coupling member side, the edge portion being the front end side portion of the second cylinder section, a portion of the second cylinder section other than the edge portion is arranged to face the heater unit with a gap therebetween, the edge portion of the coupling member is joined with the heater unit via a welded part formed by melting at least part of the edge portion of the coupling member by the laser welding; the first cylinder section is welded to and connected with the housing to have a first radius and to be formed in a tubular shape along the axis line; the second cylinder section is welded to and connected with the heater unit at the edge portion to have a second radius smaller than the first radius and to be formed in a tubular shape along the axis line. a housing in a cylindrical shape that is extended in a direction of an axis line; a heater unit in a rod shape that has a rear end part placed in the housing and a front end part protruded from a front end of the housing and is movable along the direction of the axis line; a coupling member in a thin film shape that enables the heater unit to move along the direction of the axis line and couples the heater unit with the housing; and a pressure sensor that detects a pressure based on a load transmitted via the heater unit, wherein the coupling member includes a second cylinder section and a joint section; the glow plug being characterised in that: the coupling member includes a first cylinder section that is formed in a tubular shape along the axis line; an edge portion of the coupling member and the heater unit are joined together by laser welding performed from a coupling member side, the edge portion being the front end side portion of the second cylinder section, a portion of the second cylinder section other than the edge portion is arranged to face the heater unit with a gap therebetween, the edge portion of the coupling member is joined with the heater unit via a welded part formed by melting at least part of the edge portion of the coupling member by the laser welding; the first cylinder section is welded to and connected with the housing to have a first radius and to be formed in a tubular shape along the axis line; the second cylinder section is welded to and connected with the heater unit at the edge portion to have a second radius smaller than the first radius and to be formed in a tubular shape along the axis line. the coupling member includes a first cylinder section that is formed in a tubular shape along the axis line; an edge portion of the coupling member and the heater unit are joined together by laser welding performed from a coupling member side, the edge portion being the front end side portion of the second cylinder section, a portion of the second cylinder section other than the edge portion is arranged to face the heater unit with a gap therebetween, the edge portion of the coupling member is joined with the heater unit via a welded part formed by melting at least part of the edge portion of the coupling member by the laser welding; the first cylinder section is welded to and connected with the housing to have a first radius and to be formed in a tubular shape along the axis line; the second cylinder section is welded to and connected with the heater unit at the edge portion to have a second radius smaller than the first radius and to be formed in a tubular shape along the axis line.