The present invention relates to an insulation material fixing device for an apartment house applying preload between insulation materials to constantly maintain an attachment force. The insulation material fixing device for an apartment house comprises : a cutting unit (22); a spring storage unit (24); a rod withdrawal groove (26); a guide bracket (30); an extension rod (34); a spring seat (36); a preload spring (37); a slide pin (38); a stud plate (40); a front side guide groove (44); a guide ring (50); a rear side guide groove (54); a locking protrusion (46); an elastic hook (56); a preload control plate (70); internal sawteeth (57); external sawteeth (73); a polygonal boss (74); a fastening hole (76); a stud bolt (41); a polygonal hole (41h); and a nut (80).COPYRIGHT KIPO 2016