The pig house has ramp roof comprising heat insulating layer and glass top and double-layer wall with heat insulating material between the layers. The heat insulating roof has ventilation windows. The floor of the pig house slopes down toward the middle part and has dung exhausting drain at the lower part. The present invention solve the problem of warming pig house in winter and cooling in summer, eliminate damp, cold and poor ventilation in pig house and reduce pollution in pig house.