SEAT BELT BUCKLE DEVICE

The present invention relates to a seat belt buckle device and includes: a buckle assembly (20) which locks/unlocks a tongue plate (40); an upper cover (10) which accommodates the buckle assembly (20) at the inside; and a lower cover (30). The buckle assembly (20) includes: a base frame (21) which is mounted on and combined with the lower cover (30); a latch component (22) where one end is supported to be rotated by both side of the base frame (21), and which is inserted into a combining hole (41) of the tongue plate (40); an ejector assembly (23) which locks/unlocks the latch component (22); and a release button (24) which unlocks the tongue plate (40). The ejector assembly (23) gets in linear contact with a moving rib (2191) at both sides of an ejector moving space (219), which is formed at a bottom plate (212) of the base frame (21), and moves in the forward/backward direction. The seat belt buckle device according to the present invention enables combining ends at both sides of a moving component, which is prepared at the ejector assembly of the buckle assembly, to get in linear contact with the moving rib of the base frame, thereby minimizing frictional resistance between the moving component and the base frame.