The study investigates upgrading in Vietnam's garment industry. The approach used is the global value chain theory. Unit value analysis and qualitative methods are two major methods to investigate the upgrading of Vietnam's garment industry in the global garment value chain. The major findings are first, Vietnam has achieved process upgrading which has lead to high export values even in the post MFA era. Second, in exporting to the US market, the industry has successfully upgraded in terms of product upgrading. Third, the leading Vietnamese producers has carried out functional upgrading but limited to designated FOB which is identified by these producers' limited role in assembling garments and purchasing textiles from suppliers nominated by foreign buyers.Those findings provide supports for arguments on upgrading of developing country producers in the global garment value chain (that is, developing country producers can achieve significant product upgrading but limit in functional upgrading) and on the role of East Asian traders in upgrading process of developing country's garment producers. Those traders provide less upgrading opportunities for producers' upgrading than do global buyers and regional traders.