Geographical distance constitutes friction of searching research collaborators. Taking advantage of a quasi-natural experiment featured by recently connected High-Speed Railway (HSR) lines in China, this paper seeks to identify the impact of a substantial improvement in intercity transportation infrastructure on collaborative innovation across cities, with a focus on university-industry collaboration. The data pertain to a universe of patent applications filed by all universities and colleges in China and their citations during the 1985-2016 period. Using the city-level and applicant pair-level datasets, a variant of the difference-in-differences (DID) model is employed to tease out the causal relationship between HSR and collaborative innovation. We find that HSR contributes to a substantial increase in collaborative patent applications between university and industry and the associated citations. The induced effects are salient in research partners with a closer technological distance or located within a 3-hour to 5-hour HSR traveling distance. Besides, HSR contributes to industry collaboration by utilizing universities’ strong academic disciplines into the related technological fields. Lastly, we find that HSR facilitates universities to search for new research partners with better quality beyond the geographical boundary. The searching of corporate partners is disproportionately affected.