The utility model provides a coal -fired furnace of environmental protection and energy saving, coal -fired furnace furnace body top center sets up the cooking mouth, set up flue gas discharge pipe infurnace body top one side, the inside central authorities of furnace body set up the pyrolysis gas ization pipeline, for the pyrolysis gas ization district in the pyrolysis gas ization pipeline, thebelow of pyrolysis gas ization pipeline is the semicoke combustion area, the slope of semicoke combustion area below sets up the grate, the furnace body bottom is equipped with a wind import, set up overgrate air preheated passage at the furnace body lateral wall, the air intercommunication of introducing is imported with a wind to overgrate air preheated passage bottom entry, overgrate air preheated passage upper portion is equipped with the overgrate air export, be the flue gas combustion area between overgrate air preheated passage and the pyrolysis gas ization pipeline. The utility model discloses setting up the pyrolysis gas ization pipeline at the furnace body center, making pyrolysis gas ization go on under higher temperature, pyrolysis gas in case produce is heated promptly, and then flows to the semicoke combustion area, can the condensation not produce tar, can effectively solve the higher problem of coal -fired furnace flue gas tar content.