Debris flows are abrupt geological hazards frequently resulting in destructive disasters in mountain areas. Thus, analysis of the acceptable risk of debris-flow disasters should be attentively considered, whereas the crucial problem of the acceptable disaster risk is how to know what the risk levels of debris-flow disasters are acceptable for the public. Thence, the questionnaire investigation of the acceptable risk preferences for different populations in various regions can be such a solution. The acceptable disaster risks are not only taking into account people's acceptance, but also related to government's disaster-reduction strategy and also referred to expert’s professional evaluation. Therefore, the establishment of guidelines and criterions for the acceptable risks of debris-flow disasters need all participations from multiple populations and different regions. In this survey, three-category populations including ordinary people, experts/scholars and administrators across China joined the questionnaire investigation. Five indicators (disaster-affected toll, death toll, death rate, personal direct economic loss, and total direct economic loss) were used to describe the acceptable risks of debris-flow disasters. Incorporated with frequency analysis, this work has explained the demographic characteristics for the acceptable risk preferences. The results indicate that ordinary people have relatively low acceptable risks, experts/scholars have slightly high acceptable risks and administrators have acceptable risks between both of them. Educational level, occupation, and income were the dominatingly demographic factors for the interpretations of the acceptable risk preferences.