Public perception of the underlying causes of anthropogenic climate change is a complex and subjective issue that is critical to effective risk communication. This issue is important to scientists and policymakers because of the role of individual perceptions in influencing their protective behaviour towards risk (e.g., the adoption of climate risk reduction and mitigation strategies). This cross-sectional study elucidated people's perceptions of the underlying causes of human-induced climate change in coastal communities in Cambodia and Tanzania. The multinomial logistic regression model was based on a geographically and demographically stratified national sample of 3,706 individuals conducted between March and September 2013. The distribution of the fundamental causes of anthropogenic climate change in the pooled sample was deforestation (29%), overpopulation – births and immigration (18%), greenhouse gas emissions (12%), illegal resource extraction (14%), and God's will and transgressing cultural norms (26%). Few people in both countries believed that, the usual suspect, greenhouse gas emission was the fundamental cause of anthropogenic climate change. The number of poor rural residents who indicated that deforestation was the major underlying cause of climate change was approximately three times more than members of the same sub-group who noted that greenhouse gas emissions were the underlying cause of climate change. People who had tertiary education were less likely to consider God's will and transgressing cultural norms as the underlying cause of anthropogenic climate change rather than attributing it to greenhouse gas emissions. Therefore, it is imperative to mainstream climate change into educational curricula in both countries.