To provide an arm cover free from local feelings of pressure and fastening, excellent in wearability, heat retaining properties and fashion and useful for desk work by attaching an elastic material of rubber, etc., on a trunk part of the body of an arm cover with appropriate spaces to form bellows.

A trunk part 2 of the body 1 of an arm cover is composed of a cylinder having changing parts 4 located at appropriate positions where sewing states are changed, and uniquely colored and designed. On the trunk part 2, an elastic material 3 of rubber, etc., is placed along the peripheral direction of the trunk part 2 at plural positions with appropriate spaces to form bellows. Further, the elastic materials 3 of rubber, etc., is preferably placed spirally on the trunk part 2.