Municipal　solid　waste　incineration　(MSWI)　is　an　important　part　of　energy　recovery　and　sustainable　development,　constructing　the　model　of　controlled　object　is　the　basis　of　studying　its　optimal　control.　MSWI　is　a　typical　multiinput　and　multi-output　industrial　process,　which　has　many　uncertain　characteristics　such　as　strong　nonlinearity　and　multivariable　coupling.　To　solve　this　problem,　a　model　of　controlled　object　in　MSWI　process　is　proposed　in　this　paper.　Firstly,　the　MSWI　process　based　on　grate　incinerator　is　analyzed　to　summarize　its　relevant　variables　and　control　requirements.　Secondly,　the　solid　phase　and　gas　phase　of　MSWI　process　are　divided　to　construct　material　balance　equations　of　subsystems.　Next,　the　energy　transfer　process　in　incinerator　is　deduced　and　calculated　through　thermodynamic　laws.　Finally,　the　validity　of　the　model　is　verified　by　the　process　data　of　a　MSWI　plant　in　Beijing,　China,　which　lays　a　model　foundation　for　the　study　of　the　optimal　control　of　MSWI　process.