To provide a ventilator which can carry out a huge volume of ventilation that brings about an exhilaration feel, a refreshing feel, and a natural feel occurring when outdoor air touches the skin of a person in a room.

According to the structure of the ventilator, a first opening 2 on the outside of the room, and a second opening 3 on the inside of the room are formed in a door by a ventilating stile 10, and both the openings 2, 3 are arranged almost in parallel with each other outside and inside of the room and at linear locations. Further opening/closing operation of the openings 2, 3 are carried out by on-off operation of a lock portion 5 by handling a handle 4, and an interlocking 8 for interlocking between a first cover 6 and a second cover 7. By virtue of this structure, when the first cover 6 and the second cover 7 are opened, a huge volume of outdoor air directly enters the room via the second opening 3 to touch the skin of the person in the room, which brings about an exhilaration feel, a refreshing feel, and a natural feel on the person.