Theodosia can refer to:

People

• Theodosia (given name), a given name, including a list of people with the name
• Theodosia of Tyre, 3rd century Christian martyr
• Theodosia (fl. 6th century), first wife of Liuvigild, Visigothic King of Hispania and Septimania
• Theodosia of Constantinople, 7th–8th century Byzantine nun, martyr and saint of the Eastern Orthodox Church
• Theodosia, wife of Leo V (c. 775–c. 826), Empress consort of Leo V the Armenian

Places

• Feodosiya, sometimes spelled Theodosia or Feodosia, a city in Crimea (currently disputed between Ukraine and Russia)
• Feodosiya municipality
• Theodosia, Missouri, a village in the USA
• Theodosia Inlet, an inlet in the South Coast region of British Columbia, Canada
  • the Theodosia River, a river feeding that inlet
• Dumbarton in Scotland, which was given the name Theodosia in the highly-successful forgery De Situ Britanniae

Animals

• Theodosia (beetle), a genus of beetles

Ships

• Theodosia (ship)
• HMS Theodosia

Fictional characters

• Theodosia Burr Alston, in the book My Theodosia by Anya Seton
• Theodosia Throckmorton, main character in Theodosia and the Serpents of Chaos, a children's novel by R.L. LaFevers
  • The television series based on the novel, Theodosia
• Theodosia, from the play The Royal Master by James Shirley