A remote controlled actuator includes an elongated spindle guide section (3), a distal end member (2) fitted to the distal end thereof for alteration in attitude, and a drive unit housing (4a) connected with a base end of the spindle guide section (3). The distal end member (2) rotatably support a spindle (13) holding a tool (1). The spindle guide section (3) includes a rotary shaft (22) for transmitting a rotation of the spindle (13) and an attitude altering member (31) for altering the attitude of the distal end member (2) both within an outer shell pipe (25) forming an outer shell. The attitude altering member (31) is reciprocally movably inserted in a guide pipe (30) within the outer shell pipe (25). A guide pipe restraining unit (50) is provided for restraining the guide pipe (30) from moving within the outer shell pipe (25).