A glow plug (100; 100a) 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 (180; 108a) in a thin film shape that is connected at one end with the housing and at the other end with the heater unit and is configured to enable the heater unit to move along the direction of the axis line and couple 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 (180; 180a) includes: a first bend (183; 183a) and a second bend (184; 184a) folded in the direction of the axis line; and a joint section (185; 185a) in a tapered shape configured to connect the first bend (183; 183a) with the second bend (184; 184a) and reduce diameter toward a rear end side of the housing, wherein the first bend (183; 183a) is located closer in a direction orthogonal to the axis line to the housing than the second bend (184; 184a) and is located closer in the direction of the axis line to a front end side of the housing than the second bend (184; 184a), and the first bend (183, 183a) has a greater bend radius than a bend radius of the second bend (184; 184a); characterised in that the coupling member (180; 180a) further includes: a first cylinder section (181; 181a) connected with the housing, configured to have a first outer diameter and formed in a cylindrical shape along the direction of the axis line; and a second cylinder section (182; 182a) connected with the heater unit, configured to have a second outer diameter that is smaller than the first outer diameter and formed in a cylindrical shape along the direction of the axis line, wherein when a side of the axis line is specified as inward and an opposite side to the axis line is specified as outward in a radial direction orthogonal to the axis line, the first bend (182; 183a) is formed to be connected with an opposite end of the first cylinder section (181; 181a) that is opposite to an end connected with the housing and to be folded inward in the radial direction, and the second bend (184; 184a) is formed to be connected with an opposite end of the second cylinder section (182; 182a) that is opposite to an end connected with the heater unit and to be folded outward in the radial direction. 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 (180; 108a) in a thin film shape that is connected at one end with the housing and at the other end with the heater unit and is configured to enable the heater unit to move along the direction of the axis line and couple 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 (180; 180a) includes: a first bend (183; 183a) and a second bend (184; 184a) folded in the direction of the axis line; and a joint section (185; 185a) in a tapered shape configured to connect the first bend (183; 183a) with the second bend (184; 184a) and reduce diameter toward a rear end side of the housing, wherein a first bend (183; 183a) and a second bend (184; 184a) folded in the direction of the axis line; and a joint section (185; 185a) in a tapered shape configured to connect the first bend (183; 183a) with the second bend (184; 184a) and reduce diameter toward a rear end side of the housing, wherein the first bend (183; 183a) is located closer in a direction orthogonal to the axis line to the housing than the second bend (184; 184a) and is located closer in the direction of the axis line to a front end side of the housing than the second bend (184; 184a), and the first bend (183, 183a) has a greater bend radius than a bend radius of the second bend (184; 184a); characterised in that the coupling member (180; 180a) further includes: a first cylinder section (181; 181a) connected with the housing, configured to have a first outer diameter and formed in a cylindrical shape along the direction of the axis line; and a second cylinder section (182; 182a) connected with the heater unit, configured to have a second outer diameter that is smaller than the first outer diameter and formed in a cylindrical shape along the direction of the axis line, wherein a first cylinder section (181; 181a) connected with the housing, configured to have a first outer diameter and formed in a cylindrical shape along the direction of the axis line; and a second cylinder section (182; 182a) connected with the heater unit, configured to have a second outer diameter that is smaller than the first outer diameter and formed in a cylindrical shape along the direction of the axis line, wherein when a side of the axis line is specified as inward and an opposite side to the axis line is specified as outward in a radial direction orthogonal to the axis line, the first bend (182; 183a) is formed to be connected with an opposite end of the first cylinder section (181; 181a) that is opposite to an end connected with the housing and to be folded inward in the radial direction, and the second bend (184; 184a) is formed to be connected with an opposite end of the second cylinder section (182; 182a) that is opposite to an end connected with the heater unit and to be folded outward in the radial direction.