In　the　background　of　＇carbon　peak,　carbon　neutrality＇,　it　is　crucial　to　lowering　buildings’　heating　and　cooling　energy　consumption　in　northern　China.　In　this　study,　an　underground　office　for　postgraduate　students　in　Beijing　is　selected　as　the　research,　and　EnergyPlus　is　used　for　simulation.　This　paper　compares　the　differences　in　heating　and　cooling　energy　demand　between　aboveground　and　underground　buildings　under　three　different　internal　gain　conditions.　Two　underground　structures　are　considered　in　this　paper:　fully　earth-sheltered　structure　and　semi-covered　underground　structure　with　a　shaft　outside　the　exterior　walls　that　connects　to　the　outside　environment.　And　three　internal　gain　settings　are　considered　in　this　paper:　no　internal　gain,　internal　gains　set　by　the　current　standard　(Design　standard　for　energy　efficiency　of　public　buildings　GB50189　—　2015),　and　internal　gains　set　by　measured　value.　Results　show　that　both　underground　structures　can　achieve　energy　saving,　semi-covered　structures　have　greater　potential　for　energy　saving,　up　to　19.11%.　©　2023　IBPSA.All　rights　reserved.