The invention provides a cushion to help blood circulation of lower limbs, which not only has massage effect but ensure activity of a user. The cushion comprises: an upper casing 10 passing through a rotary hole 13; a lower casing 20 arranged lower than a wall body 11 of the upper casing 10; and rotary ball units 40 formed by assembling a rotary ball 30 inside the upper and lower casing and in a state of exposed from the rotary hole 13 with one side when the upper casing 10 and the lower casing 20 are assembled. The cushion with the rotary ball 30 thereof is knitted by connecting a plurality of rotary ball units 40 zigzag in a first connection groove 14 and a second connection groove 15 disposed in the upper casing 10. By providing the freely rotary ball 30 protruding upwards, the invention can help blood circulation of lower limbs, and obtain massage effect, which not only prevents various chronic diseases, but neatly ensures activity of the user. |