Mari Simmulson (1911-2000) was an Estonian-Swedish ceramicist and sculptor, known for her work at both Gustavsbergs Porslinsfabrik and Upsala-Ekeby. She trained at Konstfack in Tallinn and worked for a time at Arabia in Finland before moving to Sweden in 1944. At Gustavsberg she collaborated with Wilhelm Kåge, but in 1949 she joined Upsala-Ekeby, where she created some of her most famous works, including sculptures, vases and dishes.