Sunscreen assembly

A sunscreen assembly is provided comprising a sunscreen (3) with two opposite lateral edge regions (4,5) which are slidingly housed in corresponding guides (6,7) extending along said lateral edge regions (4,5) of the sunscreen (3), and a rotatable winding tube for the sunscreen (3). The lateral edge regions (4,5) have a self-locking configuration allowing an easy introduction of said lateral edge regions (4,5) into the corresponding guides (6,7) but withstanding the retraction therefrom. A specially adapted winding tube for such a sunscreen (3) is provided.