Anna Maria Augusta Cassel was a Swedish artist who focused primarily on landscape painting. Her practice involved the use of both oil and tempera to capture the diverse topography of regions including Norrland, Skåne, Västmanland, and the areas surrounding Stockholm.

Cassel is frequently noted in art historical contexts for her collaborative relationship with Hilma af Klint. She was a member of the group known as The Five (De Fem), a circle of women artists who engaged in spiritualist practices and automatic drawing, which significantly influenced the development of early abstract art in Sweden.

While her own landscape work remains a distinct part of her oeuvre, recent scholarly interest in the circle surrounding Hilma af Klint has brought renewed attention to Cassel's role within this pioneering group of artists.