Mosab Hassan Yousef (Arabic: مصعب حسن يوسف; nicknamed "The Green Prince"; born 5 May 1978) is a Palestinian who worked undercover for Israel's internal security service Shin Bet from 1997 to 2007.
Shin Bet considered him its most valuable source within the Hamas leadership. The information Yousef supplied prevented dozens of suicide attacks and assassinations of Israelis, exposed numerous Hamas cells, and assisted Israel in hunting down many militants, and incarcerating his own father, Hamas leader Sheikh Hassan Yousef. In March 2010, he published his autobiography titled Son of Hamas.In 1999, Yousef converted to Christianity, and in 2007 he moved to the United States. His request for political asylum in the United States was granted pending a routine background check in 2010.