Mitigating environmental problems requires behavioural changes by individuals throughout the world, especially in rapidly developing economies (e.g., China, India) where environmental problems are worse than in wealthy or extremely poor nations. Previous studies have attempted to explore the relationships between materialism and pro-environmental attitudes and behaviours in developed countries or regions, and consistent results were obtained. Specifically, higher levels of materialism lead to lower levels of ecologically relevant attitudes and activities. However, studies using samples from developing countries have yielded inconsistent findings. The current study aimed to improve the methodological limitations in the previous studies and provide both individual and regional-level evidence from China (a representative developing country) to clarify the relationships between materialism and pro-environmental attitudes and behaviours. Using data from the World Value Survey and the Chinese General Social Survey, we observed that materialism was negatively associated with pro-environmental attitudes (Study 1, n = 2,300) and pro-environmental behaviours such as saving energy and water (Study 2, n = 3,672). Based on the findings of Studies 1 and 2, we searched for additional regional evidence in Study 3. After analysing data from 31 provinces and municipalities in China, we found that the more materialistic regions are, the more energy is consumed. Drawing on SDT, the present research provided evidence to support the hypothesis that people in a developing country (e.g., China) with higher levels of materialism are less likely to protect the environment and even have a tendency to harm the environment by consuming more energy. We conclude with a discussion of the theoretical and practical implications of the research findings.