Katerina Lemmel, née Imhoff (born 1466 in Nuremberg; died March 28, 1533 in Maihingen; also Katharina Lemmel, Katharina Lemlin) was a successful patrician businesswoman in Nuremberg who became a Birgittine nun at the monastery of Maria Mai in Maihingen in Nördlinger Ries. A collection of letters that she wrote from the monastery to her relatives in Nuremberg permits multifaceted insights into life in a late-medieval female monastery and into its system of spiritual economies.