A loop hanger for a seat belt (10) which slidably hangs a seat belt webbing (S) is provided with a base member (20) made of a metal plate and having a slot (21) through which the seat belt webbing (S) is moved, wherein the slot (21) is constituted with a long side portion (21a) extending in a generally horizontal direction and a pair of left and right short side portions (21b) communicating with left and right end portions of the long side portion (21a) and extending downwardly, a portion of the base member (20) surrounded by the long side portion (21a) and the pair of short side portions (21b) is curved smoothly from a side of the long side portion (21a) in a generally C-shaped sectional configuration, and a curved face (21f) formed by curving the portion of the base member (20) serves as a portion (20a) through which the seat belt webbing (S) is turned back. Accordingly, anti-gum up property can be improved largely.