Taking　advantage　of　the　thermal　inertia　of　a　building　to　shift　the　cooling　load　during　a　demand　response　(DR)　period　is　an　important　strategy　for　commercial　buildings.　However,　researchers　have　consistently　ignored　the　effects　of　the　thermal　inertia　of　air-conditioning　systems　on　the　DR　potential　of　buildings.　This　study　focused　on　the　coupling　effect　of　a　building　and　an　air-conditioning　system.　This　paper　describes　the　construction　of　a　coupled　thermal　inertia　model　of　a　building　and　an　air-conditioning　system,　which　was　validated　experimentally;　analyzes　the　accuracy　of　the　thermal　inertia　of　a　building　solely,　as　well　as　the　accuracy　of　both　the　building　and　air-conditioning　system　together　by　comparing　the　model　and　experiment　results;　and　quantifies　the　DR　contributions　of　the　thermal　inertia　of　both　the　building　and　the　air-conditioning　system.　A　considerable　demand　reduction　effect　of　the　thermal　inertia　of　the　air-conditioning　system　was　found,　and　the　results　of　coupling　the　thermal　inertia　of　both　the　building　and　air-conditioning　system　showed　greater　accuracy.　(C)　2018　Elsevier　B.V.　All　rights　reserved.