Elisabeth Pepys (nee Marchant de Saint Michel; 23 October 1640 – 10 November 1669) was the wife of Samuel Pepys, whom she married in 1655, shortly before her fifteenth birthday.
Her father, Alexandre Marchant de Saint Michel, was born a French Roman Catholic but later converted to the Church of England.
He married Dorothea, the daughter of Sir Francis Kingsmill, in Ireland.
Elisabeth was born at or around Bideford in Devon on 23 October 1640.
She died of typhoid on 10 November 1669.
Elisabeth was second cousin once removed to the writer Anne Kingsmill Finch.