Gertrude of Brunswick, Markgräfin of Meißen
Gertrud of Brunswick (German: Gertrud von Braunschweig; c. 1060 – 9 December 1117) was Countess of Katlenburg by marriage to Dietrich II, Count of Katlenburg, Margravine of Frisia by marriage to Henry, Margrave of Frisia, and Margravine of Meissen by marriage to margrave Henry I.

She served as regent of the County of Katlenburg during the minority of her son Dietrich III of Katlenburg in 1085, as regent of the Margrave of Frisia during the minority of her son Count Otto III of Northeim in 1090, and as regent of the County of Northeim during the minority of her son Otto III of Northeim in 1103. She was also one of the leaders of the insurrections against Emperor Henry IV and his son Henry V.