Following the emergence of social, environmental, and public health issues, this study analysed the determinants of nascent social entrepreneurial behaviour. This research investigated the effects of empathy and prior experience with social problems on nascent social entrepreneurial behaviour through social entrepreneurial self-efficacy, outcome expectations of social entrepreneurship, and perceived social support. Through utilising the quantitative survey method, this study gathered a total of 560 valid responses, comprising 258 Chinese respondents and 302 Taiwanese respondents. Outcome expectations and perceived social support positively influenced nascent social entrepreneurial behaviour for the Chinese sample, whereas social entrepreneurial self-efficacy and perceived social support positively influenced nascent social entrepreneurial behaviour for the Taiwanese sample. This research enriches the existing literature by taking account of social entrepreneurial behaviour, instead of merely analysing social entrepreneurial intentions.