The utility model discloses a metal -air battery belongs to the metal -air battery field. It includes battery heap and electrolyte circulation dispenser, electrolyte circulation dispenser includes electrolyte tank and pump body assembly, the battery monomer including a plurality of series connection is piled to the battery, the battery monomer includes electrode support and plate electrode, the lower extreme that the battery is piled still is equipped with backward flow temporary storage device, be equipped with in the electrode support perpendicularly to electrolyte circulation canal, circulation canal is including holding chamber, perpendicular delivery port and water inlet, pump body assembly respectively with the water inlet is linked together with backward flow temporary storage device, perpendicular delivery port with the backward flow temporary storage device be linked together, perpendicular delivery port runs through to electrode support's bottom from electrode support's upper end. The utility model discloses a set up in the battery monomer perpendicularly to electrolyte circulation canal, form a plurality of parallelly connected return circuits at the battery in -pile, avoid producing each other the influence of blockking up.