Harb (Arabic: حرب) is a large Sunni Tribe in the Arabian peninsula. There is no official tribe population count but it is estimated to be approximately four million in Saudi Arabia. It is originally a Qahtani tribe. Several authentic sources on Arab tribes genealogy state that the great-grandfather of Harb tribe is Harb ibn Saad ibn Saad ibn Khawlan ibn Amr ibn Qadha'ah ibn Himyar ibn Qahtan.
Harb tribal lands extend from the Red Sea coast in Tihamah (Western Part of Saudi Arabia) to the heart of Najd in the central region of Saudi Arabia, and from North the Harbi lands extend from Madinah (a holy city for Muslims) to Al Qunfudhah in the south. The tribe's reach extends to other countries like Kuwait, Iraq, Egypt and UAE .