Abstract: With the increase of countries joining “the Belt and Road” initiative, the export trade volume of agricultural machinery products between China and countries along “the Belt and Road” has steadily grown. This paper selects the export trade data of agricultural machinery products of 121 countries along “the Belt and Road”, uses the stochastic frontier gravity model to explore the factors affecting the export of agricultural machinery products, and calculates the export trade efficiency and trade expansion space. The import indicative comparative disadvantage index is used to measure the dependence of agricultural machinery products in the importing countries. Based on the two indicators of trade expansion space and dependence on agricultural machinery products, the Boston Matrix is used to analyze the export prospects of China’s agricultural machinery products to countries along “the Belt and Road”. The results show that the economic size, the population size, and the common language of the country have significant positive effects on the export of agricultural machinery products. The quality of communication and logistics infrastructure, as well as bilateral trade agreements, significantly improve trade efficiency. Africa, Asia, and North America have high potential for trade expansion. Trade prospects between China and the countries along “the Belt and Road” remain broad.