Margaretha Kirch (b. ca. 1703, d. after 1744) was a German astronomer.
She was the daughter of the astronomers Gottfried Kirch and Maria Margarethe Kirch and the sister of Christfried Kirch. She and her sister Christine Kirch were educated in astronomy from the age of ten and worked as the assistants of their brother. Kirch did the calculations and assisted in the observations for Christfried Kirch.
- M. Ogilvie, J. Harvey, eds., The Biographical Dictionary of Women in Science – Pioneering Lives from Ancient Times to the Mid-20th Century: Volume 1 A-K. Routledge, New York and London 2000, ISBN 0-415-92039-6, pp. 1774–1775.
- R. Wielen, Thomas Hockey (Ed.): Bibliographical Encyclopedia of Astronomers. Springer, New York, 2007, ISBN 978-0-387-31022-0, p. 638.
- D. A. J. Seargent: The Greatest Comets in History: Broom Stars and Celestial Scimitars. Springer, New York, 2009, ISBN 978-0-387-09512-7, pp. 116–119.