Catherine of Saxe-Lauenburg (c. 1400 – 22 September 1450), was a Baroness consort of Werle-Güstrow, a Duchess consort of Mecklenburg, and Regent of the Duchy of Mecklenburg from 1422 to 1436 as the guardian of her under age sons.
Catherine was the daughter of Eric IV and Sophia of Brunswick-Lüneburg.
When John died in 1422, after six years of marriage, she ruled until 1436 as Regent for her minor sons.
For a long time, a charter date July 1448 was the last known document to name Catherine.
Around the turn of the Century, Hans Witte could finally prove she died on St. Maurice day (22 September) 1450.