To provide a thermal overload relay always acquiring an approximately single setting current adjustment value to the screwed position of an adjusting screw regardless of the rotating direction of the adjusting screw.

The thermal overload relay comprises a contact opening/closing mechanism for opening/closing a fixed contact and a movable contact installed in a housing; an interlocking bar displaced according to a current value of a main circuit; an adjusting mechanism installed in a swingable manner in the housing and transmitting the displacement of the interlocking bar to the contact opening/closing mechanism to operate the contact opening/closing mechanism and also adjusting the setting current value of a main circuit for operating the contact opening/closing mechanism by swinging displacement; the adjusting screw screwed penetrating a housing wall and swinging the adjusting mechanism according to the screwing quantity. A recess is formed at the tip part of the adjusting screw, and a spherical body is held between the recess and the adjusting mechanism.