This study was carried out to design and develope conveyer combustion type coal heater in the green house. Different from existing coal heater, the conveyer combustion type coal heater was designed for circulating coal from supplying to exhausting. The size of traveling grate and velocity reduction gear ratio for driving traveling grate were designed to product coal heater had 200,000kcal/hr heating capacity. The result is that the coal heater of 200,000kcal/hr heating capacity was determined by the width of grate in between 600 to 800㎜ when the horizontal length of conveying combustion area was 1,500㎜. And the first and second reduction ratio of 1:100 and 1:70 was more effective at 1,350rpm, respectively, in the coal heater of 200,000kcal/hr heating capacity.