Over the last two decades, the People's Republic of China has provided record amounts of international development finance and established itself as a financier of first resort for many low- and middle-income countries. China's international development finance commitments now average $85 billion annually, roughly double those of the U.S. Yet very little is known about the environmental risks posed by the infrastructure projects that China has financed. Many have questioned whether China is sufficiently prudent in its design and implementation of large-scale infrastructure projects. There is particular concern about the siting of projects funded by the Chinese government, particularly those that facilitate legal and illegal logging, agricultural frontier expansion, and human settlements in previously remote or pristine areas. We study the siting and impacts of Chinese government-funded road improvements in Cambodia, where over the past two decades China's state-owned banks have supplied more than $4 billion for 30 projects building, rehabilitating or upgrading over 3,000 km of major roadways. Cambodia's forests contain some of the most biologically diverse habitats in the world, and have experienced dramatic deforestation over the past two decades.