The utility model discloses a running sock which comprises a sock body, the sock body comprises a main body weaving part and a
foot arch weaving part, the main body weaving part and the
foot arch weaving part are connected together and form a containing cavity used for containing a foot, the
foot arch weaving part corresponds to the position of a foot arch, and the foot arch weaving part corresponds to the position of the foot arch. The foot arch weaving part is of a tuck stitch structure formed by interweaving mixed
yarn, the mixed
yarn comprises first
yarn and second yarn which are interwoven, the first yarn is elastic yarn, or the first yarn and the second yarn are both elastic yarn. Compared with the prior art, the mixed yarn is tensioned by adopting a tuck stitch structure, so that the elasticity of the arch knitting part in the front-back direction is limited, and the elasticity of the arch knitting part in the left-right direction is reserved, and therefore, when a runner runs, the arch knitting part is not easy to slide due to the fact that the elasticity is limited in the front-back direction; therefore, the arch is supported and protected.