Fluid frictional hot-water system consisted of power supply equipment, a motor, fluid heater, fluid tank, circulating pump, fan, flow meter and a heat exchanger. The system had a motor of power capacity 15.2kw/h, light-oil hot air heater in control plot had the heating capacity 20,000kcal/h, by the performance test result, it could supply heat from 24.6 to 28.1 kw depending on the motor, respectively. Thermal efficiency of fluid frictional heater were 88.1% to 91.0% in the same conditions. As the result, a deviation of indoor air temperature between the treatment plot and the control plot was about 2℃. It was heating cost of the each system heater and light-oil hot air heater heating cost were 742,200won, 2,266,000won. therefore heating cost saving was 67%. Yield of tomato cultured in greenhouse with fluid frictional hot-water system was high as 4%. As a result, the fluid frictional hot-water system was 48% higher in economics than the hot air heater.