Abstract: This invention relates to a sectional steel-frame structure and a method of construction using the same in which vertical members, horizontal members and brackets may be assembled to form a lattice, thus keeping the frame structure and performing arrangement construction more rapidly and conveniently. By using the sectional steel-frame structure, it becomes possible to simultaneously perform the construction of insulation boards and interior/exterior materials as well as concrete pouring work so that the construction period and construction expenses such as labor cost, subsidiary materials cost and the like may be considerably reduced.