The Banu Qaynuqa (Arabic: بنو قينقاع; Hebrew: בני קינקאע; also spelled Banu Kainuka, Banu Kaynuka, Banu Qainuqa, Banu Qaynuqa) was one of the three main Jewish tribes living in the 7th century of Medina, now in Saudi Arabia. In 624, the great-grandfather of Banu Qaynuqa tribe is Qaynuqa ibn Amchel ibn Munshi ibn Yohanan ibn Benjamin ibn Saron ibn Naphtali ibn Hayy ibn Moses and they are descendant of Manasseh ibn Joseph ibn Jacob ibn Isaac son of Abraham. They were expelled during the Invasion of Banu Qaynuqa, after breaking the treaty known as the Constitution of Medina.
In the 7th century, the Banu Qaynuqa were living in two fortresses in the south-western part of the city of Yathrib, now Medina, having settled there at an unknown date. Although the Banu Qaynuqa bore mostly Arabic names, they were both ethnically and religiously Jewish. They owned no land, earned their living through commerce and craftsmanship, including goldsmithery. The marketplace of Yathrib was located in the area of the town where the Qaynuqa lived. The Banu Qaynuqa were allied with the local Arab tribe of Khazraj and supported them in their conflicts with the rival Arab tribe of Aws.
In September 622, Muhammad arrived at Yathrab now called as Medina with a group of his followers, who were given shelter by members of all indigenous tribes of the city who came to be known as the Ansar. He proceeded to set about the establishment of a pact, known as the Constitution of Medina, between the Muslims, the Ansar, and the various Jewish tribes of Yathrab to regulate the matters of governance of the city, as well as the extent and nature of inter-community relations. Conditions of the pact, according to traditional Muslim sources, included boycotting the Quraysh, abstinence from "extending any support to them", assistance of one another if attacked by a third party, as well as "defending Medina, in case of a foreign attack".