Gertrude of Flanders may refer to:

• Gertrude of Flanders, Duchess of Lorraine (d. 1115/26), daughter of Robert I, Count of Flanders
• Gertrude of Flanders, Countess of Savoy (1112–1186), daughter of Thierry, Count of Flanders
• Gertrude of Flanders (Blackadder), fictional character in the popular BBC sitcom Blackadder

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