The invention relates to an artificial wet land biomass feeding channel device. A biomass feeding channel is divided into two regions; the front section is a biomass feeding region which comprises a biomass feeding area, a gravel layer and a grait layer in sequence from top to bottom; the rear section is a grait layer; the front section and the rear section are separated through a brick wall and a perforated tracery wall; the biomass feeding channel adopts U-shaped water distribution; sewage sequentially passes through the front section and the rear section of the biomass feeding channel and then finally enters an artificial wet land bed body. The biomass feeding channel can realize concentrated feeding of biomass, so that enough carbon sources can be supplied to the wet land, and the denitration efficiency of the wet land is improved. Aiming at the unavoidable problem of blocking in an artificial wet land biomass carbon source feeding process, the biomass feeding channel provided by the invention can enable the blocking to occur at a fixed point; during engineering running, the biomass feeding channel is regularly cleared, so that the wet land blocking problem can be effectively controlled; even if the biomass feeding channel is blocked, water flow can pass through the biomass feeding channel in an overflow manner and finally enter the artificial wet land, so that the normal running of the wet land is not affected.