Purpose -Debates in the literature on entrepreneurship concentrate on whether the focus should be on psychological variables or the external environment. Despite most studies being on the former, many others argue that the external environment is more useful in understanding business start-ups. This paper seeks to examine the relative influence of both types of variables. Design/methodology/approach -Data were collected from 337 Chinese respondents in three different groups: first, people who do not want to start a business; second, people planning to set up a business; and finally, entrepreneurs who had started successful businesses. Respondents were assessed on three psychological/behavior variables (achievement striving, social networking/Guanxi, and optimism), and one external environment variable (perceived importance of a favorable business environment). Findings -Group comparisons revealed that psychological characteristics as well as the business environment were both significant predictors. Psychological characteristics were a stronger influence for potential entrepreneurs and the business environment stronger for successful entrepreneurs.Research limitations/implications -The results help clarify debates regarding the relative importance of personal characteristics and the business environment to entrepreneurial motivation as these variables explained 54 percent of the variance for motivation. Although only one ethnic group (the Chinese) was studied, the results for the personality variables largely matched those in the Western literature, which suggests generalizability of the findings. Also, the environmental influence measure could be valuable in future research. Originality/value -Both psychological characteristics and an environmental measure are evaluated to compare their influences on entrepreneurial motivation.