A shock absorber according to the present invention includes: a shock absorber main body having an outer shell and a rod; and a knuckle bracket attached to an outer circumference of the bottom end of the outer shell. The knuckle bracket includes: a holding portion having a cylindrical shape with a C-shaped cross section, and that holds the outer circumference of the outer shell; a pair of attachment portions extending radially outwards, and in parallel with each other, from respective circumferential ends of the holding portion; and reinforcing portions formed by bending top ends of the attachment portions in directions approaching each other; and a C-shaped welded portion having a C-shaped surface that is formed by top ends of the reinforcing portions and a top end of the holding portion, the C-shaped welded portion being formed by welding the C-shaped surface to the outer shell, across a range from a position spaced from one circumferential end of the C-shaped surface, traversing across an upper part of a rear side of the holding portion, to the other circumferential end of the C-shaped surface.