Wilhelmina Carolina Gravallius, née Isaksson (7 September 1807, Mogata – 22 November 1884, Botkyrka), was a Swedish writer.
She was born to parish vicar Carl Peter Isaksson and Anna Hallberg, and supported herself as a governess until 1846.
She debuted with the novel Högadals prostgård (1844), which was a success.
During her marriage to the vicar in Thoresund Christian Gravallius in 1846-1861, she was inactive as a writer.
After his death, she moved to Stockholm and resumed her career.