Rural households in Asian developing countries such as Vietnam have been participating in non-farm activities for decades, yet impacts beyond the economy of these households are little understood. Using evidence from available literature and two case studies from rural Vietnam, this paper exposes a range of socio-cultural impacts of non-farm activities. An increased social tension driven by a widening economic gap between poor and better-off households or ethnic majority and minority groups was the most frequently reported impact in the literature. The case studies reveal additional impacts, notably those associated with public security, preservation of local culture, and safety of farm households with migrants during and following climate-related disasters. An increasing number of young migrants who exited family farms to access non-farm jobs partially led to the latter two impacts. The rural development and poverty reduction policies of Vietnam enacted in the past two decades (2000–2020) that promoted livelihood diversification had limited measures addressing socio-cultural impacts of non-farm activities. An amendment of these two categories of policies for the implementation beyond 2020 or a strengthened synergy in implementation with other categories of policy such as social policies is necessary to ensure sustainable rural development in Vietnam.