A glow plug with a pressure sensor including a heater member (4) having a heating element (9) disposed therein and projecting from a forward end of a metallic shell (2), a center rod (3) having, at its forward end, a connection portion (3A) to which a rear end portion of the heating element (9) is connected, and an annular clearance CR formed between the metallic shell and the heater member in a region located on the forward end side of a junction portion (14A) of a deformable member (14) joined to the heater member. A portion of the heating element located on the forward end side relative to the forward end of the connection portion is at least partially located on the radially inner side of the clearance CR, and the forward end of the connection portion is located on the forward end side relative to the forward end of the junction portion.