Metal-organic　cages　(MOCs)　are　a　class　of　compounds　formed　through　the　coordination　of　metal　ions　with　organic　ligands　to　create　well-defined　and　cage-like　structure.　These　unique　structures　offer　versatile　environments　for　catalyzing　a　wide　range　of　chemical　reactions.　The　catalytic　capabilities　of　MOCs　are　significantly　influenced　by　the　nature　of　the　metal　ions,　functional　ligands,　and　the　cage　structure.　Notably,　the　confined　spaces　within　MOCs　can　lead　to　enhanced　reaction　efficiencies,　particularly　in　processes　such　as　light-induced　hydrogen　generation　and　the　photocatalytic　reduction　of　CO2.　Furthermore,　MOCs　show　great　potential　in　photo-organic　synthesis　due　to　the　cage　structure,　which　provides　a　confined　environment　and　allows　for　encapsulating　organic　molecules,　making　them　useful　for　improving　the　selectivity　and　efficiency　of　catalytic　process.　This　review　reports　the　development　of　MOCs　for　photocatalysis,　focusing　on　the　structural　design　and　regulation　strategy　to　build　functional　MOCs　for　photocatalytic　hydrogen　production,　CO2　reduction,　organic　transformation.　Insights　into　the　photocatalysis　are　discussed　including　the　challenges　and　further　research　direction　in　MOC-based　photocatalysis.