D31 is a state road in central Croatia connecting Velika Gorica and Glina to Croatian motorway network at the A11 motorway Velika Gorica - jug (south) interchange.

[1][maps 1] The road also serves as a connection to the A3 motorway via D30 state road.

The road is 56.2 km (34.9 mi) long.

[2] The road, as well as all other state roads in Croatia, is managed and maintained by Hrvatske ceste, state owned company.

[3] Traffic is regularly counted and reported by Hrvatske ceste, operator of the road.