To provide a tobacco smoke guard device for the interior of a room which can protect a user from tobacco smoke, which floats indoors, by a simpler architecture.

The tobacco smoke guard device for the interior of the room includes a tube-shaped housing 13, which has an inlet port 14 formed at the lower part end and an exhaust port 15 formed at the upper part end, and a ventilation means, which is arranged within the housing and leads to the outside air inhaled from the inlet port from the exhaust port, and the housing has a position holding means so that the inlet port can be arranged and fixed to the lower part than the breast of a user.