State Road 121 (Serbia)

State Road 121, is an IIA-class road in northern Serbia, connecting Croatia at Sot with Bosnia and Herzegovina at Jamena. It is located in Vojvodina.

Before the new road categorization regulation given in 2013, the route wore the following names: M 18.1 and P 128 (before 2012) / 117 and 115 (after 2012).

The existing route is a regional road with two traffic lanes. By the valid Space Plan of Republic of Serbia the road is not planned for upgrading to main road, and is expected to be conditioned in its current state.