Ivar Axel Henrik Arosenius (October 8, 1878 – January 2, 1909 from the complications of haemophilia), was a Swedishpainter and author of picture books. In the latter capacity he is most noted for the book Kattresan (The Cat Journey), which was published after his death. He lived in the village of Älvängen, north of Gothenburg. After his death, his house fell into disrepair and was finally demolished. He is buried at Östra kyrkogården in Gothenburg.
In Älvängen, one of the schools, Aroseniusskolan, is named after Ivar Arosenius.
Nowadays, some of Ivar Arosenius' paintings can be seen at the Museum of Art in Gothenburg.