This study aims to analyse the factors affecting the Micro, Small, and Medium Enterprises in the province of South Sumatra, Indonesia. Data of 100 MSMEs were collected through questionnaires in the 15 regencies/cities in South Sumatra. The statistical analysis used was Structural Equation Modelling (SEM) processed through AMOS. The results evidence that the external factors of capital support, business partners, and infrastructure directly have no direct effects but indirectly affect the performance of MSMEs in South Sumatra. Also, the availability of resources and environmental conditions; and the capability of business owners and employees indirectly affect the performance of MSMEs in South Sumatra. Lastly, the use of technology and research impact the performance of MSMEs in South Sumatra directly and indirectly through the availability of resources and environmental conditions and business owners and employees' capability. Theoretically, this study expands the MSMEs literature by discussing factors (i.e., external and internal) affecting MSMEs' performance holistically. Practically, this study is beneficial for the government, practitioners, and policymakers.