SIDE AIRBAG ASSEMBLY

The present invention relates to an improved side airbag assembly capable of preventing free movement of a tether during deployment of an airbag. The side airbag assembly includes an airbag (100) built into a seat of a vehicle and deployed outward from the seat, a tether (200) disposed on an outer surface of the airbag and configured to control free movement of the airbag when the airbag is deployed, and a guide patch (300) disposed on the outer surface of the airbag and coupled to the tether, and the guide patch allows the tether to pass therethrough at least twice.