Photocatalytic　nonoxidative　coupling　of　CH4　to　C2H4　with　a　high　rate　and　selectivity　is　considered　challenging　and　impractical　due　to　complex　chemical　pathways　and　unfavorable　thermodynamics.　This　work　introduces　a　strategy　of　tandem　photocatalysis　based　on　Au　and　Pd　nanoparticles　codeposited　on　a　Bi2NbO5F　photocatalyst,　which　divides　the　CH4　to　C2H4　reaction　into　two　distinct　steps　carried　out　in　tandem　by　multiple　activity　components,　i.e.,　CH4　coupling　to　C2H6　on　Au　and　C2H6　dehydrogenation　on　Pd.　As　a　result,　the　optimized　Au-Pd/Bi2NbO5F　shows　CH4　coupling　to　C2H4　with　a　high　yield　of　22.6　mu　mol　g-1　h-1　and　selectivity　of　63%　under　simulated　solar　light　irradiation.　The　reaction　pathway　is　investigated　by　a　series　of　activity　experiments　and　in　situ　characterizations,　demonstrating　separate　steps　on　Au　and　Pd.　This　work　proposes　a　general　strategy　for　the　future　design　of　photocatalysts　to　drive　complex　reactions　efficiently　and　selectively　based　on　the　concept　of　a　tandem　system.