The　simultaneous　epitaxial　growth　of　vertical　nanorod　arrays　and　thin　films　of　zinc　oxide　(ZnO)　was　realized　on　a　gold-plated　plane　sapphire　substrate　via　a　simple　chemical　vapor　deposition　method.　In　this　nanostructure,　the　vertical　single　crystal　nanorods　are　hexagonal　prism　or　cylindrical　in　shape,　and　are　all　grown　on　a　ZnO　thin　film,　so　that　the　vertical　nanorods　are　connected　to　each　other　through　the　beneath　thin　oxide　ZnO　film.　In　comparison　with　ZnO　nanofilms,　the　prepared　nanostructure　has　excellent　photoelectrochemistry　(PEC)　performance　with　an　incident　photocurrent　efficiency　of　2.4　times　that　of　the　simple　ZnO　nanofilms;　while　its　light　energy　conversion　efficiency　is　5　times　that　of　ZnO　nanofilms.　Its　excellent　PEC　performance　can　be　attributed　to　its　high　surface　area-to-volume　ratio　and　the　carrier　transport　channel　provided　by　the　supporter　ZnO　film.　The　mechanism　for　cooperative　growth　of　ZnO　nanorod　arrays　and　thin　films　was　proposed　as　follows:　during　the　processing,　Au　liquefies　and　absorbs　Zn　atoms　in　the　atmosphere　forming　alloys.　After　the　alloy　droplets　were　supersaturated　ZnO　begins　to　nucleate,　and　then　ZnO　film　formed　on　the　surface　of　the　substrate.　At　the　same　time,　Zn　autocatalyzed　(vapor-solid)VS　growth　and　Au　catalyzed　(vapor-liquid-solid)VLS　growth　occurred,　respectively　forming　hexagonal　prism　nanorods　and　cylindrical　nanorods,　and　finally　a　vertical　nanorod　array　was　connected　through　the　underneath　thin　ZnO　film.　©　2022　Chinese　Journal　of　Materials　Research.　All　rights　reserved.