The division of Cassini is a space located between the rings has and B of planet Saturn. She was discovered in 1675 by the astronomer Jean-Dominique Cassini. According to récentes ^{measurements,} its limit interns is located at 117  500 km of the Saturn center and its external limit with 122  000 km. It is thus broad of 4  500 km. Other figures are also published: 117  580 and 122  170 km or 117  500 and 122  200 km.

Recent studies showed that the division of Cassini is a zone where the density of the particles is lower than in the neighbouring rings and not a place empties matter. It seems that the gravitational attraction of Mimas is the cause: the division of Cassini being in resonance with the orbit of the satellite, the successive passages of Mimas eject probably them materials located in the division of Cassini (Goldreich and Tremaine 1978). There is not however unanimity on this explanation.

The Saturn's rings have other similar divisions, like the Division d’ Encke or that of Keeler, but the division of Cassini is largest and can be observed without difficulty with a small telescope.

Many images showing the division of Cassini, the Saturn's rings and Saturn itself are available on the site of the Cassini-Huygens mission.