A rotary brush for automatic vehicle washing systems, said brush comprising a central unit (2) and a plurality of cleaning elements (3), operatively supported by and coupled to said central unit (2) through removable coupling means (7); the cleaning elements (3) being removable from said central unit (2) and it being possible to replace and/or remove them without requiring the removal of said central unit from the rotary structure; said central unit (2) comprises a rigid shaft (4) that supports a plurality of supporting elements (5) comprising a plurality of lugs (53) to which the cleaning elements (3) are fastened; the rotary brush is characterized in that said cleaning elements (3) comprise bands (33), fringed and fringeless, helically arranged on said central unit (2) in such a way that each band (33) is coupled to a plurality of supporting elements (5).