Ernst Jonas Jonsson (September 30, 1873 – March 14, 1926) was a Swedish sailor who competed in the 1908 Summer Olympics and in the 1912 Summer Olympics.
In 1908 he was a crew member of the Swedish bost Freja which finished fifth in the 6 metre class competition.
Four years later he was part of the Swedish boat Sass which finished fourth in the 6 metre class competition.