The present invention relates to a method for adjusting a focus position in an iris recognition system, the method including the steps of: projecting a designated light for measuring a distance between the user and a camera; acquiring user images including the image projected by the light; and measuring a distance between the user and the camera by extracting the projected image by the light out of the user images and analyzing characteristics of the image. In addition, the present invention relates to an apparatus for adjusting a focus position in an iris recognition system, which enables to adjust the focal angle of an iris, the apparatus includes an illumination device; an iris recognition camera for acquiring user images having an iris image when the illumination device irradiates a light; an illuminator for helping the user with the focal angle according to sharpness of the visible ray that depends on the focal angle by transmitting a visible ray from the illuminator and by reflecting the user images.