Flood risk management has become important more than ever, because an escalating threat of unpredictable and extreme weather is affecting flood-prone communities. People-centred risk communication has been proposed as an effective strategy that can stimulate people to protect themselves against flood risks. However, little research with a sound theoretical underpinning has been done to examine the effectiveness of such a strategy in developing countries. We use a field experiment to analyse how risk communication can influence households’ intentions to implement mitigation measures. Our results show that communicating about the risk of floods and how to cope with floods significantly increased both threat and coping appraisals, and thereby motivated households to take more non-structural measures. While formal risk communication had certain direct effects on mitigation intention, informal risk communication percolated through psychological variables. Risk communication should focus on coping capacities for financial measures and address the problems of wishful thinking and disaster subculture of flood-prone households. Furthermore, women's participation in risk communication did not change the intentions to take mitigation measures of the male household heads in the Vietnamese Mekong Delta.