BACKGROUND: The human microbiome is an essential factor of physical and mental health, yet the general population has little knowledge about it. This survey explores public familiarity with the human microbiome and (potential) public preferences related to monitoring and improving one's microbiome health. The study also examines whether recognizing the importance of one's microbiome may promote a more ecosystem-aware perspective towards microorganisms. METHODS: We conducted an online survey with nationally representative samples from France, Germany, South Korea, and Taiwan (N = 2860). The results were interpreted using descriptive statistics and network analysis. We also performed a t-test to compare perceptions of microorganisms before and after a short reflection on the role of human microbiome for one's body and health. RESULTS: In our data, most respondents express willingness to monitor the health of their microbiome (especially, in the European countries) and to adjust their lifestyle such as diet and exercise to improve it. A paired samples t-test shows a slight positive shift in perceptions of microorganisms and the microbial world after the reflection exercise compared to baseline. CONCLUSIONS: The study shows that the public recognize the essential role of the human microbiome in health and are willing to take care of it, which may have implications for public health policy. Our findings also suggest that stronger awareness of the human microbiome may promote lifestyle change and a more encompassing environmental outlook.