Actively　promoting　the　energy　consumption　transition　(ECT)　and　realizing　green　growth　is　a　critical　way　for　China　to　achieve　its　sustainable　development　goals,　and　it　is　also　a　core　task　for　the　current　economic　development　of　Chinese　cities.　Therefore,　we　explore　the　spatial　effect　of　ECT　on　green　total　factor　productivity　(GTFP)　through　the　spatial　Durbin　model　(SDM)　via　balanced　panel　data　from　279　prefecture-level　cities　in　China　from　2007　to　2019　and　reveal　the　heterogeneous　characteristics　of　this　relationship.　In　addition,　we　investigate　their　nonlinear　relationship　characteristics.　The　results　of　the　study　are　as　follows.　(1)　ECT　significantly　enhances　GTFP　with　an　obvious　spatial　spillover　effect.　(2)　ECT　in　the　eastern　region　(EAR)　positively　affects　GTFP　in　both　local　and　neighboring　cities,　but　the　spatial　spillover　effect　in　the　central　region　(CTR)　is　not　significant,　and　the　western　region　(WER)　has　a　suppressed　spatial　spillover　effect.　(3)　ECT　in　resource-based　cities　(RCs)　positively　affects　GTFP　in　both　local　and　neighboring　cities.　However,　its　spatial　spillover　effect　is　not　significant　in　non-　resource-based　cities　(non-RCs).　(4)　The　results　for　the　double-threshold　effect　show　a　nonlinear　relationship.　Only　after　crossing　the　second　threshold　does　ECT　contribute　significantly　to　GTFP.　Formal　environmental　regulation　(FER)　and　informal　environmental　regulation　(IER)　are　nonlinear　characteristics　of　the　ECT　and　GTFP.　Moreover,　we　find　that　IER　has　a　greater　effect　on　the　relationship　than　FER　does.　This　research　provides　an　effective　reference　for　China　to　move　toward　green　growth.