PURPOSE: To provide an electronic part mounting machine capable of correctly photographing and identifying the grasping condition of an electronic part.

CONSTITUTION: A movable mirror transfer mechanism 40 is provided on the electronic part mounting mechanism 1 of an electronic part mounting machine, and the grasping condition of an electronic part by the electronic part mounting mechanism 1 is photographed and identified by a camera via a movable mirror 3 etc. In the movable mirror transfer mechanism 40, when the movement of the direction X1 of the electronic part mounting mechanism is stopped, the inertia force of the direction X1 of a movable mirror 3, a ball screw shaft 44, and a ball screw 42 is applied to a belt 48b, the inertia force of the direction X1 of a mass body 52 is applied to the belt 48b, and pulleys 46a and 45b are not rotated to effectively restrain the movement of the movable mirror 3 along the ball screw 42. Consequently the grasping condition of an electronic part can be correctly photographed and identified to be corrected.