Background/Objectives: This study aims to study the impact of the entrepreneurial mentality of social small and medium-sized entrepreneurs on the sustainability of SMEs through the intermediary effect of the Korean government-backed policy for social enterprises in South Korea.Methods/Statistical analysis: The target of the study is the CEO of a social small and medium-sized business company that has been in business for less than seven years, and the survey method was conducted. The questionnaire item was composed of a total of 35 questions, including five demographic questions, the measurement was used for a Likert 5-point scale. Using SPSS 22.0 as an empirical analysis was carried out technical statistical analysis, exploratory factor analysis, reliability analysis, regression analysis, mediated analysis.Findings: Looking at the results of the study, first, the empathy, social value orientation, and innovation of the entrepreneurial spirit of social start-ups have been shown to affect the sustainability of social SMEs. Social value orientation has the greatest impact (β = .345***). Second, Empathy, Social value orientation, and Innovation have been shown to influence government policy support, but risk-taking has not been affected. Social value orientation has the greatest impact (β= .459***). Third, the Republic of Korea Government Support Policy has been shown to have an impact on sustainability (β= .751***). Fourth, about the impact of Social SMEs Entrepreneurship and sustainability, innovation and Risk-taking is partly mediated by Government Support Policy, while Empathy (p=.158) and Social value orientation (p=.148) was found to be a complete mediating.Improvements/Applications: In this study, which mediated government-funded policies on the impact of the entrepreneurial mentality of the CEO of a Social SMB, empathy and Social value orientation were identified as important factors. Therefore, it is believed that a study will be needed on the optimal configuration scenario of the Government Policy Support System of the Republic of Korea, which takes into account social entrepreneurship.