The present disclosure provides a breathing structure for a lighting fixture, and a lighting fixture comprising the breathing structure. The lighting fixture includes a lamp body which has an inner cavity. The breathing structure includes: a mounting portion, arranged on the lamp body and protruded from the lamp body; a through hole, formed in the mounting portion, the through hole penetrating the mounting portion and being communicated with the inner cavity of the lamp body; a breathable film, arranged on one end of the through hole facing towards an outside of the lamp body; a washer, arranged on the breathable film and provided with a vent slot; and an elastic fastener, fastened on the mounting portion and configured to compress the washer towards a direction of the inner cavity of the lamp body.