Facing the historical opportunities and challenges brought by the new round of digital technology revolution and industrial transformation, promoting common development and narrowing the technological gap with frontier countries through high-level cooperation is a key path for the majority of latecomers to achieve leapfrog development. Against the background of the “Digital Silk Road” Initiative, this paper uses data from 2010 to 2023 at the country level along “the Belt and Road” to empirically study the impact of digital technology cooperation among countries along “the Belt and Road” on technological catch-up and its mechanisms. The findings are as follows:first, digital technology cooperation among countries along “the Belt and Road” can promote the narrowing of the technological gap with frontier countries and facilitate technological catch-up. Second, mechanism tests indicate that digital technology cooperation mainly affects the enhancement mechanisms such as basic research and development, technology transfer, and technology application to stimulate the “chain innovation effect”, promoting technological catch-up by enhancing the level of the innovation chain. Third, heterogeneity analysis reveals that the promoting effect of digital technology cooperation on technological catch-up is significant in larger-scale countries and those with higher levels of digital infrastructure along the route. Fourth, as the core driver of digital technology cooperation along “the Belt and Road”, China can exert a “pulling effect” to drive countries along the route to achieve technological catch-up. The narrowing of cultural and institutional differences significantly enhances China’s “pulling effect” on technological catch-up among countries along the route, and this effect is more significant for smaller-scale countries and those with higher levels of digital infrastructure. Therefore, countries along “the Belt and Road” need to deepen digital technology cooperation, optimize strategic layout, strengthen innovation resource sharing, and enhance multilateral coordination mechanisms to effectively promote common leapfrogging of technological gaps and achieve technological catch-up.