Using　DeST　Program,　Simulation　of　Space　Heating/cooling　Load　of　two　buildings　has　been　conducted　for　Geo-Space　Heating　System　using　Gradient　Utilization　Techno-　logy　in　university　campus.　Simulations　were　conducted　in　accordance　with　the　different　conditions:　Temperatures　&　RH　of　Rooms,　different　sources　of　Weather　Data,　intensity　of　persons,　Timetable　of　operation　&　Equipment,　building　constructions.　Also　measurement　has　been　conducted　using　the　measurement　system.　Then　the　comparisons　between　simulation　&　measurement　were　made.　The　range　values　of　(HPF)Sys.h　was　3-13,　average　value　was　6-9　based　per　hour;　The　values　of　(HPF)Sys.d　&(EER)Sys.h　could　be　obtained　through　the　comparison　between　measurement　&　simulation.　(HPF)Sys.d　values　were　obtained　around　4~7,and　(HSPF)Sys　was　around　5-6　for　winter　2005-2006　&　2006-2007.　In　2006　summer,　consumption　of　electrical　energy　was　obtained;　(EER)Sys.d　values　based　on　per　day　was　2.5~5.3.In　accordance　with　the　analysis　of　(HPF)Sys.d　&(EER)Sys.d　the　lower　data　always　appeared　in　the　periods　of　non-peak　&　lower　load.　It　tells　us　where　the　potential　of　energy　saving　will　be.　The　researchers　noticed　the　quite　difference　between　the　simulation　&　measurement&　&　try　to　search　the　reasons.　More　efforts　&　more　suggestions　will　be　made　for　increasing　the　values　of　(HSPF)Sys&(SEER))Sys　of　the　systems.