Purpose　Steered　by　upper　echelon　theory,　this　study　aims　to　scrutinize　the　prevalence　of　project　manager　demographic　factors　(age,　education　and　experience)　in　project　sustainability　management　and　project　performance.　Design/methodology/approach　We　used　a　sample　of　209　project　managers/supervisor/team　leaders　who　were　working　in　the　projects　of　the　China-Pakistan　Economic　Corridor　(CPEC).　Findings　The　results　indicate　that　project　manager　demographic　factors　have　a　significant　influence　on　project　performance　(except　experience)　and　project　sustainability　management.　Moreover,　project　sustainability　management　partially　mediates　the　relationship　between　age,　education　and　project　performance　while　it　fully　mediates　the　path　between　experience　and　project　performance.　Practical　implications　The　research　recommends　senior,　high　educated　and　experienced　managers　for　CPEC　who　promote　sustainability　and　gain　high　project　performance.　Originality/value　A　number　of　studies　have　been　carried　out　to　assess　the　relationship　between　top　managers＇　attributes　and　environmental　activities.　However,　so　far,　none　of　the　studies　has　paid　attention　to　the　CPEC　and　projects　working　in　Pakistan.