A　series　of　porous　ZnO/SnO2　heterojunction　photocatalysts　with　different　Sn　contents　were　successfully　synthesized　through　a　simple　one-pot　solvothermal　method.　The　evolution　of　particle　size,　composition,　texture　structure,　and　photocatalytic　performance　as　a　function　of　Sn　content　was　systematically　studied.　It　is　found　that　the　as-synthesized　ZnO/SnO2　heterojunction　photocatalysts　show　much　higher　photocatalytic　activity　than　ZnO,　SnO2,　SnxZn1-xO2,　and　ZnO/Zn2SnO4.　Photocorrosion　of　ZnO　was　observed,　for　all　samples　that　contain　ZnO　nanocrystals,　during　the　photocatalytic　process.　The　photostability　of　ZnO/SnO2　samples　containing　small　ZnO　nanoparticles　were　significantly　enhanced.　The　most　photostable　ZnO/SnO2　sample　exhibits　at　least　6.5　times　higher　photostability　than　pure　ZnO　sample.　It　is　proposed　that　the　photocatalytic　activities　and　photostability　of　the　ZnO/SnO2　photocatalysts　are　determined　by　the　photogenerated　carrier　transport　rates　at　the　SnO2-ZnO　and　ZnO-electrolyte　interfaces.