The aim of this study is to provide information about the influence and impacts of Social Media Marketing (SMM) in promoting Micro, Small, and Medium Enterprises (MSMEs) in Indonesia. The approach of this study is quantitative research with data collection method using the electronic questionnaires of Google forms and collected 163 respondents. The respondents of this research are some of the owners of MSMEs in Jakarta and Tangerang. The measurement model of outer and inner model is analysed by SmartPLS software. In this study, Structural Equation Model was being used to test the relations of each construct. Findings of the study show that SMM positively mediates the relationship between Perceived Usefulness and Impact on Business, SMM positively mediates the relationship between Perceived Ease of Use and Impact on Business, SMM positively mediates the relationship between Compatibility and Impact on Business, SMM negatively mediates the relationship between Facilitating Conditions and Impact on Business, SMM positively mediates the relationship between Cost and Impact on Business, and SMM has a positive Impact on Business.