A moving speed control method of an optical element switching device including a fixing member, a moveable member having a plurality of recess portions configured to hold one or more optical elements, a driving device supported to the fixing member and configured to move the moveable member, and an engaging mechanism supported to the fixing member and configured to be engaged to the recess portion to thereby position each of the one or more optical elements on an optical axis, the moving speed control method includes: starting to move the moveable member from a state where the recess portion is engaged to the engaging mechanism; accelerating a moving speed of the moveable member; decelerating the moving speed when the engaging mechanism is to be engaged to the next recess portion; and making the moving speed zero when the engaging mechanism is engaged to the recess portion.