The present invention relates to a side curtain typed air bag in order to prevent passengers from being injured by a side glass window or structure of a vehicle in the event of a rollover or rolling of the vehicle. The side curtain typed air bag of the present invention is characterized in that the upper and lower portions of air bag consisting of thermoplastic multi-filaments are combined by sewing, and a rubber component is coated or an adhesive film is laminated on upper portions and/or lower portions of air bag including sewing portion, an air leak amount per unit length of the sewing portion (measured at pressure of 2.5 KPa) is less than 0.8L/min. cm. The air bag of the present invention can safely protect passengers in the event of a rollover of the vehicle by suppressing the air leak.