GLOW PLUG

Breakage in a short period is suppressed by improving a heat dissipation property. In a glow plug that includes: a heater element (10) that is inserted in a combustion chamber of an internal combustion engine; a housing (14) that supports the heater element in a state where a heating section of the heater element is projected; a resilient body (31) that couples the heater element and the housing to divide a space between the heater element and the housing into a tip side and a rear end side of the housing; and a pressure sensor (15) that is provided in a space on the rear end side of the resilient body in the housing to detect a pressure in the combustion chamber from displacement of the heater element, a space (142) on the tip side of the resilient body in the housing is filled with a heat transfer material (22) that is melted by heat transferred from the heater element.