To provide a ventilation system for houses intended for solving such problems that a conventional ventilation system for houses which is set with a fan and/or a ventilator on both surfaces crossing at right angles in the longitudinal direction intends for maintaining a house environment through introducing outside air, exhausting inside air based thereon, but as having no insect net, the system remains scheming air flow in a house, and air flow in the whole house is not necessarily sufficient.

This ventilation system for houses comprises setting a fan and/or a ventilator on both the gable walls of a house, and stretching one or a plurality of insect nets on the inside of both the gable walls so as to introduce outside air to the house through the fan and the insect net on one side, and secure air flow in the nearly horizontal direction and wide air flow in the longitudinal direction of the house through the insect net on the other side and the insect net, and the insect net on the other side and the ventilator.