On Feburuary 22, 2012, the WTO case of China's export restrictions on raw materials was settled as the Appellate Body report was adopted. The report decided that China's export restraints were inconsistent with its commitments under several agreements.This was the first case that the Appellate Body made a judgement on a case dealing with export restrictions. This paper examines effects of the WTO dispute settlement process for this case using the metal price data. We first review the WTO dispute settlement process and a brief history of the China's export restrictions case. This WTO case is important by two reasons. First, the WTO had been mainly dealing with import restrictions that might prevent smooth trade between nations. Secondly, the targeted commodities were mineral resources neccessary for the wide range of manufactural products. Hence the judgement would probably give a significant impact on many industries. Then, we evaluate the effects of the WTO dispute settlement process by event studies of alminium and zinc prices. We find that the alminium price is not affected, however, the zinc price fell down when the Appellate Body report was adopted. The results of alminium and zinc suggest that the effect of the WTO dispute settlement process might depend on the difference of the production shares of China.