A protective grille for a fan has a web structure which comprises radial webs spaced apart in a circumferential direction and coaxial circumferential webs spaced apart in a radial direction. The protective grille has at least a radial outer region and a central region around a central axis of the protective grille. An envelope surface spanned by the radial outer region and the central region is of convexly curved form in the radial outer region and is of flat form, parallel to a radial plane of the protective grille, in the central region.