Abstract: Floor heating system is an effective way to save energy in the greenhouse, which utilizes its heat in a rational way and heats only the local area of plants growing on the floor. The temperature above canopies is at a lower level, so the heat consumption in the greenhouse is reduced. An experiment was developed to investigate the thermal environment in a potflower greenhouse which using a floor heating system. The results of the experiment showed that there was better temperature distribution in the greenhouse. In north-south horizontal direction, the temperature difference was about 1℃; the vertical temperature from floor to screen gradually decreased about 1℃; and the crop root temperature was from 19℃ to 25℃ at night. The thermal environment in this greenhouse is more suitable for plant development. This paper also analyzed the energy saving and economic profit for the floor heating system, compared with the traditional heating system. 28% of energy consumption, 34.1% of heat distributor investment and about RMB30000 of annual operational costs were saved in this system.