In　the　process　of　urbanization,　a　brisk　building　boom　triggers　a　series　of　environmental　problems.　Construction　contractors　usually　present　environmentally　fraudulent　behaviors,　i.e.,　greenwashing　behaviors　(GWBs),　to　legitimize　their　activities,　ultimately　hindering　the　sustainable　development　of　the　society.　However,　the　formation　mechanism　of　the　contractors＇　GWBs　is　still　unclear.　Through　the　lens　of　fraud　GONE　theory　(i.e.,　greed,　opportunity,　needs,　and　exposure),　this　study　applies　the　multi-group　structural　equation　model　(SEM)　and　fuzzy-set　qualitative　comparative　analysis　(fsQCA)　to　examine　the　formation　mechanisms　of　GWBs.　The　results　of　SEM　show　the　relationships　between　four　fraud　factors　and　GWBs.　Additionally,　the　projects　are　grouped　into　three　categories:　government　investment　projects,　private-public-partnership　(PPP)　projects,　and　private　investment　projects.　The　results　of　multi-group　SEM　reveal　that　the　effects　of　four　fraud　factors　differ　significantly　across　projects　with　different　investment　characteristics.　The　results　of　fsQCA　suggest　that　there　are　three　typical　driving　mechanisms　for　GWBs.　Furthermore,　this　study　develops　a　project　information　transparency　framework　and　a　＂greenwashing　tree＂　to　form　a　systematic　understanding　of　GWBs.　Finally,　on　these　bases,　this　study　provides　targeted　suggestions　and　policy　recommendations　for　governing　contractors＇　GWBs.