The present invention relates to a built-in light fixture to be fitted in a suspended ceiling or similar, with a mounting ring (4) insertable into an opening in the ceiling and fixable by holding elements (6) and a light unit (3) which is attached in particular releaseably to the mounting ring (4), wherein fixed to the mounting ring (4) is a support frame (13) which defines a mounting space for the light unit (3) and has on its upper side facing away from the mounting ring (4) attachment means (18) for fixing the light unit (3) onto the support frame (13).