Iyo Railway Group Nan'yo Bus is a bus operator of the Iyo Railway Group, headquartered in Yawatahama City, Ehime Prefecture.
It was established in 1989, taking over the local routes in the Nan'yo region from Iyo Railway.
The company operates three depots: the Yawatahama Depot (its headquarters), the Kuma Depot, and the Ozu Depot. Its main service area covers Yawatahama City, Ozu City, Ikata Town, and Kumakogen Town.
The Hino Rainbow RJ was once widely used within the Iyo Railway Group fleet. However, it has gradually been retired. The last remaining unit operated by Iyo Railway Nan'yo Bus was vehicle No. 1561, which was transferred from the Nagahama Depot to the Kuma Depot.