The financial vulnerability of households effectively measures their financial risks, and the proportion of financially vulnerable households in rural areas is not only increasing year by year, but also higher than that in urban areas. Against the backdrop of the digital economy becoming an important feature of the new development stage, can digital infrastructure construction, as an important engine for promoting the development of the digital economy, alleviate the financial vulnerability of rural households? Existing literature focuses on exploring the impact of digital infrastructure construction on enterprise income and production efficiency, with less attention paid to the micro household effects of digital infrastructure construction. This article is based on the meaning and main determining factors of household financial vulnerability and theoretically demonstrates the alleviating effect of digital infrastructure construction on rural household financial vulnerability. It analyzes the impact channels of digital infrastructure construction on rural household financial vulnerability from the perspectives of non-agricultural employment and insurance participation. Furthermore, this article combines the 2010—2018 China Household Tracking Survey (CFPS) and China Urban Statistical Yearbook data, drawing on the measurement methods of household financial vulnerability proposed by Yuan Chenghe and Yu Xue (2022) and Zhang Ji et al. (2022), to calculate the financial vulnerability indicators of rural households in China. The “Broadband China” strategy is used as a quasi-natural experiment, and a multi-period DID model is applied to examine the mitigating effect of digital infrastructure construction on the financial vulnerability of rural households. Empirical research has found that the construction of digital infrastructure can effectively alleviate the financial vulnerability of rural households, and this result is still robust after considering the impact of household debt to income ratio as a substitute for household financial vulnerability, endogeneity, selective bias, municipalities, and precision poverty alleviation policies. Further analysis shows that the construction of digital infrastructure has a greater alleviating effect on the financial vulnerability of male-headed, unmarried, and low-income rural households. Moreover, the construction of digital infrastructure can alleviate the financial vulnerability of rural households by promoting non-agricultural employment and insurance participation. Compared with previous literature, the potential marginal contributions of this article are: firstly, it expands the micro household effects of digital infrastructure construction and related research on household financial vulnerability and provides a new perspective for improving the ability of rural households to withstand and cope with uncertainty. Secondly, it is revealed that the increase in non-agricultural employment and insurance participation of rural households brought about by digital infrastructure construction is an important channel to alleviate the financial vulnerability of rural households, providing specific paths and micro evidence for alleviating the financial vulnerability of rural households. Thirdly, it provides more effective policy support for policy authorities to further strengthen digital infrastructure construction and alleviate the financial vulnerability of rural households. This study to some extent reveals the inherent logic between digital infrastructure construction and the financial vulnerability of rural households, which helps government departments formulate more targeted policy measures to alleviate the financial vulnerability of rural households in the context of the booming digital economy, provide differentiated policy support for rural households with different characteristics, and more effectively prevent and resolve financial risks in rural areas.