. The purpose of this research that to test on the effect of trust to used media of electronic commercewho adoption by SMEs through assessment of the success model of information system by Delone & Mclean (2003). In addition, this research purpose too that hand over the empiric fact of the success value model information system by Delone & Mclean (2003) in connection to used media of electronic commerce (e-commerce). The populations are whole leadership or stakeholder Micro, Small, Medium Enterprises (SMEs) in Palopo City. The sample of this research take by using non probability method that approach purposive sampling with consideration that sample choose by based purpose of research that sector Micro, Small, Medium Enterprises (SMEs) by using media of electronic commerce (e-commerce). Measurement of sample take over about 200 samples, by consideration minima sample for Structure Equation Model (SEM) that 100 samples and error rate about 5 %. For test of hypothesis, this research used structural equation model (SEM) through approach Partial Least Squares (PLS-SEM) by help software Smart PLS 3. Result of research indicate that construct trust in fact capable to act kind by direct or indirect as mediation variable to used media of electronic commerce (e-commerce) who adoption by UMKM through the value success model information system of Delone & Mclean (2003). The influence of information quality, system quality, and service quality toward user satisfaction who mediated by trust those three are had indirect effect positive and significant. While trust influence positive and significant by direct toward user satisfaction. Result of next research that capable hand over empiric support toward the success model of information system by Delone and Mclean with combine construct trust in fact capable describes phenomena by using system electronic commerce (e-commerce) for SMEs in Palopo City. Where from sixteen of hypothesis who offered only six are refused and ten of hypothesis others are accepted.