中文摘要：

全球价值链分工下要素的跨境流动赋予了贸易要素含量新的内涵。文章提出了符合全球价值链分工特征的贸易要素含量测算框架，并以中美贸易为对象对Heckscher—Ohlin—Vanek（简称HOV）定理的有效性进行检验。结果表明，中美双边贸易的要素结构并不符合HOV定理的预期．中国对美国的资本净出口大于劳动净出口，且二者之间的差距在逐渐增大。美国跨国公司的FDI和中美两国劳动生产率差异导致的中国（美国）对美国（中国）出口资本／劳动比的提升（下降）是造成这一结果的主要原因。中美两国劳动要素结构体现出显著的互补性。优化要素结构，提升中高技术劳动对中国出口增加值的贡献度，是实现中国比较优势动态升级的基础。

英文摘要：

The Cross - border flow of production factors gives factor content of trade a new connotation. The paper puts forward the accounting framework of ＂factor content of trade＂ and ＂factor trade＂ that reflect the characteristics of GVCs. Take the Sino - U. S. trade as the object, the article test the validity of HOV theorem in GVCs. It turns out that the factor content of Sino - U. S. trade does not comply with the prediction of HOV theorem. The net export of capital from China to the US is larger than that of labor, and the gap between the two is getting bigger. The FDI of U. S. multinational enterprises into china and the difference of labor productivity between china and U. S. make the capital/labor ratio of china＇ s export to the U. S. rise, while making the capital/labor ratio fall in US export to china. The result also shows that the factor structure of china and the U. S. have significant complementarities. Therefore, optimizing the factor structure and improving the contribution of middle - and high - skilled labor in china export is the foundation of the dynamic upgrading of china comparative advantage.