国家形象是国家软实力的重要组成部分，基于一国的客观情况，也能在一定程度上被塑造。随着中国日益强大，国际媒体中的中国形象建构成为研究热点，但探究中国形象历时建构的研究较少。自2013年提出以来，一带一路”倡议从谋篇布局的“大写意”转入精耕细作的“工笔画”，于2018年进入高质量发展阶段，现已成为世界上最大的国际合作平台，其建设同中国形象息息相关。然而一些国家对“一带一路”的误读却会影响相关国家对中国的认知。为了探究美国主流媒体在一带一路报道中对中国形象的历时建构，本研究收集了2013年9月至2022年美国四大主流报纸有关“一带一路”的报道共310篇，通过等距抽样选取31篇报道进行批评隐喻分析。研究发现，美国主流媒体主要使用的隐喻类型为人类隐喻、战争隐喻、旅程隐喻、竞争隐喻、方位隐喻，将中国整体刻画为一个雄心勃勃的危险大国，形象较为负面。在“一带一路”进入高质量发展阶段后，美国媒体使用了比“大写意”阶段更多的战争隐喻、竞争隐喻与狩猎隐喻，建构出更坚决和富有侵略性的中国形象。

National image is an important component of national soft power. It is based on a country's objective situation and can also be shaped to a certain extent. With China’s growth and increasing global presence, the construction of China's image in international media has become a hot topic of research, but fewer studies have explored the construction of China's image over time. The Belt and Road Initiative, introduced in 2013, has shifted from the stage of high-level planning to the stage of intensive and meticulous implementation, and has entered the stage of high-quality development in 2018. Given the Initiative's close association with China's image, misinterpretations of it by other countries can impact how China is perceived. To explore the diachronic construction of China's image by the American mainstream media in the Belt and Road Initiative reports, this study collects 310 reports on the Belt and Road Initiative from September 2013 to 2022 from four major U.S. mainstream newspapers, and selects 31 reports through equidistant sampling for critical metaphor analysis. The study finds that the dominant types of metaphors used by the American mainstream media in their reports are Human metaphors, War metaphors, Journey metaphors, Competition metaphors, and UP or Down metaphors, which portray China’s image as negative, ambitious, powerful, and dangerous. Furthermore, the analysis shows that during the phase of intensive implementation, China's image is portrayed more aggressively and assertively, with a higher frequency of War, Competition, and Hunting metaphors.