A free-of-bearing rotational positioning device for a dewatering basket of a non-treading type wringer bucket, comprising: a bucket body having a projecting seat being extended from the bottom of the bucket body toward inside; a support shaft being covered and secured by the projecting seat, the upper portion thereof jutting out of the top of the projecting seat to create a connection part; a positioning element having a conic part at the top thereof, the conic part being tapered upward, a positioning surface being formed at the bottom of the conic part and extended outward from the periphery of the support shaft; and a dewatering basket having a driven seat at the center of the bottom thereof. The bottom of the driven seat includes a shaft holder made of non-metal material. In mounting the dewatering basket, the driven seat fits from top to bottom over the connection part of the support shaft. After the lower sleeve passes through positioning element in a compression manner, the positioning surface of the positioning element is stretched into the engagement groove at the center of the shaft holder when returning to its original shape.