In a curtain type safe air bag device, a gas is smoothly and rapidly supplied from an inflator to a safe air bag. The air bag (1) is slenderly folded and accommodated in a vehicle roof portion (5), then the air bag (1) is unwound to form a curtain shape. An elongated body portion (25) of the inflator (25) is accommodated in a communication road (40) for communicating a first air chamber (41) witha second air chamber (42) and arranged along the length direction of the vehicle roof portion (5). An gas port (25b) of the inflator (25) is arranged at the side of the first air chamber (41) with big volume. The communication road (40) is narrowed by the body portion (25a) of the inflator to control the gas flow, compared with the second air chamber (42), more gas is supplied to the first air chamber (41).