One holder of the first and second holders in an optical apparatus has first and second adjustment face groups. The first and second adjustment face groups respectively include a plurality of first adjustment faces and a plurality of second adjustment faces. The second adjustment face group is provided along a first rotation direction from the first adjustment face group. The other holder has first and second abutting portions respectively abutting against any one of the plurality of first and second adjustment faces. A position on the optical axis of an adjustment face arranged at an end in a second rotation direction opposite to the first rotation direction among the plurality of first adjustment faces is approximately equal to a position on the optical axis of an adjustment face arranged at an end in the first rotation direction among the plurality of second adjustment faces.