Isfrid of Ratzeburg was a Premonstratensian cleric who served as the third bishop of Ratzeburg beginning in 1179. Born around 1200, he previously held positions as a canon at Cappenberg monastery and as the Provost of Jerichow. He was recognized for his administrative talents, specifically his ability to establish various parishes and his efforts to rebuild the monastery of Floreffe after a fire. He died in Ratzeburg on June 15, 1204.