Abstract: A boiler for co-firing municipal solid waste and short timber for cultivating fungus includes a boiler chamber and fire grate, where the boiler chamber comprises a furnace, a reburning chamber and a third flue, a front arch and a rear arch are arranged on a lower portion of the furnace and located above the fire grate, and a short timber for cultivating fungus feeding device is arranged on a lower portion of a front wall of the furnace. The short timber for cultivating fungus feeding device includes a star-shaped feeding machine and a hopper, a skin expansion joint is arranged between the star-shaped feeding machine and the hopper, and an air pipe is arranged on the hopper. A layer of a plurality of boiler internal desulfurization desulfurization nozzles and two layers of a plurality of Polymer Non-Catalytic Reduction denitration nozzles are arranged in a height direction of the furnace.