A fixing apparatus includes an endless belt, a heating member configured to heat the belt, a detection unit configured to detect temperature of the heating member, a signal line connected to the detection unit, a holding member configured to hold the temperature detecting member, and an urging member configured to urge the temperature detecting member toward the heating member. The holding member includes a through hole for leading out the signal line and a contact portion being in contact with the signal line at a position located, in a width direction of the belt, between the through hole and the temperature detecting member and located, in an urging direction of the urging member, at a same position with a connecting portion between the signal line and the temperature detecting member or at a position closer to the heating member than the connecting portion.