Abstract: A method of fixedly securing an lighting fixture to a ceiling of a building structure, comprises a first securing step for securing an anchor grip at a prescribed position on a bottom face of a slab of the building structure, a flexible suspender being inserted through the anchor grip; a second securing step for securing a suspender grasping assembly temporarily to a lighting fixture support member; a suspending step for inserting the flexible suspender from the lower free end thereof through the suspender grasping assembly and then raising the suspender grasping assembly along the flexible suspender, while the lighting fixture support member is temporarily fixed to a temporary set position on the suspender; an adjusting step for adjusting height of the lighting fixture support member to fit into a ceiling finish board, by moving the suspender grasping assembly along the flexible suspender together with the lighting fixture member; and a fixing step for fixing the lighting fixture support member to the flexib