Under the background of free trade agreement，we analyze how trade policy uncertainty(TPU)affects China’s export expansion and export upgrading.We introduce trade policy uncertainty into quality heterogeneous model and deduce the related hypotheses.In order to explore TPU’s effects，we apply micro Chinese firm level data from 2002 to 2014.We find that the reduction of TPU can promote export expansion and export upgrading，mainly through OFDI channel.FTA is Chinese government’s solution to the reverse globalization wave.TPU is a new perspective to explain export expansion and export upgrading.