To perform a smooth fixing of an LED lighting fixture to a ceiling surface, to improve substantially workability and to prevent the lighting fixture from dropping without using any member after its fixing.

A groove 14 is formed by protrusion ribs 13 at a side plate 12 of a base plate 2 set with screws at a ceiling surface. Both ends of the side plate 12 are punched with first fitting holes 15. Both ends of the protrusion ribs 13 of a fixture main body 3 installed at the lower surface of the base plate 2 are punched with second fitting holes 28 at positions corresponding to the fitting holes 15. A spring engaging body 40 having an engaging piece 46 is slidably installed within the groove 14. The spring engaging body 40 is slid rightward, the engaging piece 46 of the engaging body 40 is inserted into the fitting holes 15 and 28 and protruded inward from the fitting holes 15 and 28. With this arrangement above, the fixture main body 3 can be installed easily at the base plate 2 and the fixture main body 3 can be positively prevented from being dropped from the base plate 2.