Internet　of　Things　(IoT)　technology　develops　rapidly　and　is　increasingly　used　in　the　field　of　facility　agriculture,　the　emergence　of　digital　twin　technology　provides　a　possibility　for　the　intelligent　management　of　facility　agri-culture.　In　this　study,　IoT　and　digital　twin　technologies　are　combined　to　design　a　digital　twin　system　for　mapping　multiple　environmental　variables　in　plant　factories　to　realize　the　intelligent　management　and　help　plant　factory　managers　make　intelligent　decision-making　management　schemes.　The　system　includes　a　multi-environmental　variable　parameter　acquisition　system　and　an　environment　variable　control　system　based　on　Arduino,　a　multi　-environmental　variable　data　monitoring　and　remote　environment　control　system　based　on　Android,　and　a　multi-environmental　variable　mapping　digital　twin　model.　IoT　and　computer　development　technologies　are　used　to　monitor　environmental　parameters　and　control　the　state　of　various　equipment　in　plant　factories　and　realize　the　connection　between　things　and　networks.　Digital　twin　technology　maps　the　multi-environmental　variables　of　plant　factories　to　digital　twin　and　intuitively　feeds　back　the　parameters　of　the　multi-environmental　variables　to　the　plant　factory　managers,　completing　the　connection　between　people　and　things.　By　combining　the　IoT　technology　with　digital　twin　technology,　a　digital　twin　system　based　on　multi-environmental　variable　mapping　in　plant　factory　is　established,　so　that　the　parameters　of　environmental　variables　such　as　CO2,　temperature　and　humidity　in　plant　factory　can　be　accurately　adjusted　according　to　the　different　needs　of　different　stages　of　plant　growth,　and　it　can　help　plant　factory　managers　to　realize　intelligent　decision-making.