This paper studies how immigrants in intermediate sectors affect downstream export performance. We develop a theoretical model in which a sector’s exports depend not only on its own immigrant workforce, but also on immigrant labor in input-supplying sectors. Using a new dataset on U.S. input–output from 2003-2017, we show that increases in immigrant employment in these sectors raise exports in connected downstream industries. This effect operates partly through improved production efficiency that lowers upstream input costs. By linking labor migration to production networks, we identify a new channel through which immigration shapes comparative advantage in international trade.