South Africa has been imposing anti-dumping duties on bolt and nut of China since 1999, and for more than 10 years now. In the second anti-dumping sunset review investigation, Ningbo Jinding Fastening Piece Co., Ltd. responded to lawsuits actively and achieved success, which has set an example for the industry to respond to anti-dumping actively. Therefore, this paper uses dynamic GTAP model to simulate the whole industry’s successful reaction to anti-dumping sunset review investigation, and analyzes the effect of South Africa’s cancellation of anti-dumping duties on China’s bolt and nut industry and macro-economy. The result of the study shows that South Africa’s cancellation of anti-dumping duties on China will promote the output, domestic sales and export of the bolt and nut. Meanwhile, it will also improve the trade terms of China and enhance the overall social welfare.