The agreement was signed by officials from the World Bank and Kazakhstan in Astana on October 11.
When completed, the highway will stretch some 300 kilometers and link Almaty to Khorgos.
The World Bank says that artery serves as a transit route not only for Kazakhstan and China but other Central Asian nations as well.
The World Bank says the project has the potential to boost regional trade.
The highway is an integral piece of the international motor corridor "Western Europe - Western China," a big part of which transits Kazakhstan.
The estimated date of completion of the highway is 2015.