PURPOSE:To automate control of a temperature, humidity, etc. by inputting in advance fundamental factors such as a kind, a heating value, etc. of a pigpen, in a computer of a control part, operating them together with an open air temperature, humidity, etc. detected by a sensor, and controlling an air inflow device, etc. CONSTITUTION:Environments such as a temperature, etc. of a windless pigpen 1 are adjusted automatically by use of a computer. A kind, an area and a heat transmission coefficient of the pigpen, the number of fans, a windflow quantity, a wind velocity of an air inflow port, a heating value of a pig, which are fundamental factors for controlling the environments, and the number of pigs, its average weight, a desired set temperature and humidity of the pigpen, etc., which are variation factors are inputted in advance in said computer (control part). The environments are controlled to a desired temperature and humidity by detecting and operating an open air temperature (a), a temperature (b) in the pigpen and humidity (c) in the pigpen, and controlling an air inflow device A, a ventilating fan B, a heating boiler C and a humidifying machine D.