Disclosed is a view finder for a reflex camera, so designed that the view finder is provided with an objective lens group L1, the fixed lens group L2 and the eye piece lens L3 in sequence, whereby the distance between the front lens group and the fixed lens group is constant and there is provided a first dismountable attachment lens in front of the objective lens group and a second dismountable attachment lens at the back of the objective lens group. The sign of the refractive power of the first and the second attachment lens is inverse to that of the objective lens group. The first attachment lens and the objective lens group and the objective lens group and the second attachment lens respectively form a substantial afocal lens system.