Petra Marieke Sijpesteijn (born 2 February 1971, Naarden) is professor of Arabic at Leiden University. She was the founding president of the International Society for Arabic Papyrology.
Sijpesteijn received her MA from Leiden University and her PhD from Princeton University where she won the annual departmental prize for best thesis in 2004.
Sijpesteijn was the founding president of the International Society for Arabic Papyrology (2001-2014). She is currently professor of Arabic at Leiden University.