In 2005 China provided duty-free access to 190 items from 25 least developed sub-Saharan African (SSA) countries. Three years later duty-free access was extended to 454 items from 31 SSA LDCs. We find no evidence that China's preferential market access program for the least developed sub-Saharan African countries has helped these countries gain competitive edge over other exporters into the Chinese market. While there is evidence of decreased export bundle concentration and movement up the value chain for SSA countries involved in the program, the effect differs significantly across countries.