With Ce@g-C3N4 as a heterogeneous semiconductor photocatalyst, nBu4NCl as both a redox catalyst and a hydrogen atom transfer catalyst, the first example of semiheterogeneous photocatalytic cross-dehydrogenative coupling of N-heteroarenes and alkanes/ethers with H2 evolution was developed. Both a diverse array of high-value alkylated N-heteroarenes and clean H2 can be efficiently coproduced under sacrificial reagent- and chemical oxidant/reductant-free conditions. Combining both the reversible Ce4+/Ce3+ redox pair and the reversible Cl̅/Cl ̇ redox pair can considerably improve the photocatalytic efficiency.