verbThis study is to compare the efficiency of charcoal kiln size 200 litre horizontal position of different ventilation openings. By making a comparison between charcoal kiln with vents behind the stove. With charcoal kiln with vents the bottom stove. And using bamboo size 1 pieces Length 70 cm As the fuel in the efficiency test of charcoal kilns. By testing the fuel properties on the basis of standard products. The community(มผช.). Yield comparison of wood charcoal and Charcoal wood production rate. The tests found that charcoal from charcoal kiln with vents behind the stove. There is a heat taller than charcoal kiln with vents bottom furnace The average percent 264.780 calories per gram. Which charcoal obtained from charcoal furnac with vents below the stove. There will be less moisture than the charcoal kiln with vents behind the stove. The average percent 0.013. And charcoal obtained from charcoal furnac with vents below the stove. There will The amount of ash less than the charcoal kiln with vents behind the stove. The average percent 0.000.In the production of charcoal kilns with vents below the stove will yield wood charcoal More than charcoal kilns with vents behind the stove. The average percent 4.430. But the charcoal kilns with vents behind the stove. There will the rate of wood charcoal production more than charcoal kilns with vents below the stove. The average percent 0.972. Therefore, it can be concluded that the charcoal kilns with vents below the stove efficient in producing wood charcoal the better. charcoal kilns with vents behind the stove. Due to convection from the stove front. Go to the firewood in the stove. The more the passage of smoke. (A hot wind) the more it will be good for the charcoal production. (Will get much charcoal And Complete). which The charcoal kilns with vents below the stove there is a passage of smoke (A hot wind) More than charcoal kilns with vents behind the stove.