The deal covers the construction of the Pojate-Preljina and the Novi Sad-Ruma roads with a combined length of 140 kilometres (km), the Serbian government said in a statement.
The project is financed by China's Ex-Im Bank.
Works on the 109.6 km six-lane Pojate-Preljina road could get underway in the spring of 2013 and should take four years to complete.
The project for the 27 km four-lane Novi Sad-Ruma road should be ready in 2013 and construction should take 30 months, Serbian regional development minister Verica Kalanovic said after co-signing the document.
CRBC is currently building a bridge over the river Danube in Belgrade.
($=0.7592 euro)