An electric actuator including a housing and an electric driving unit driving an output shaft supported by the housing, said electric actuator comprising: a selector member having a working end portion protruding inside the housing and an operating end portion protruding outside the housing, said selector member being rotatable about a rotation axis and movable in a direction of the rotation axis by operation of the operating end portion; a position holding member provided in a portion of the selector member to be arranged inside the housing so as to protrude in a direction intersecting the rotation axis; a detection object provided at the working end portion of the selector member so as to extend in the direction intersecting the rotation axis; a detector provided inside the housing to detect the detection object; a first engagement groove for engaging with the position holding member, provided on a cooperation surface inside the housing; and a biasing member biasing the selector member in the direction of the rotation axis to make the position holding member approach the cooperation surface, wherein the first engagement groove is formed so that the detection object is positioned in one of a detectable area where the detection object can be detected by the detector and an undetectable area where the detection object cannot be detected by the detector when the position holding member is engaged with the first engagement groove, and the detector is configured to switch between supply and cutoff of power to the electric driving unit in accordance with whether the detection object is positioned in the detectable area or in the undetectable area, characterized in that the electric actuator further comprises a second engagement groove provided on the cooperation surface and extending in a direction intersecting the first engagement groove, said second engagement groove being formed so that the detection object is positioned in the other of the detectable area and the undetectable area when the position holding member is engaged with the second engagement groove. a selector member having a working end portion protruding inside the housing and an operating end portion protruding outside the housing, said selector member being rotatable about a rotation axis and movable in a direction of the rotation axis by operation of the operating end portion; a position holding member provided in a portion of the selector member to be arranged inside the housing so as to protrude in a direction intersecting the rotation axis; a detection object provided at the working end portion of the selector member so as to extend in the direction intersecting the rotation axis; a detector provided inside the housing to detect the detection object; a first engagement groove for engaging with the position holding member, provided on a cooperation surface inside the housing; and a biasing member biasing the selector member in the direction of the rotation axis to make the position holding member approach the cooperation surface, wherein the first engagement groove is formed so that the detection object is positioned in one of a detectable area where the detection object can be detected by the detector and an undetectable area where the detection object cannot be detected by the detector when the position holding member is engaged with the first engagement groove, and the detector is configured to switch between supply and cutoff of power to the electric driving unit in accordance with whether the detection object is positioned in the detectable area or in the undetectable area,