The purpose of this research is to analyze effect of electronic word of mouth (E-WoM) and brand image on purchase decision of Samsung Brand Mobile Phones moderated by E-Trust in Undergraduate Students, Faculty of Economics and Business, Universitas Sumatera Utara, Medan City. This research is a quantitative research with an associative or relationship research design. Population in this study are Undergraduate Students, Faculty of Economics and Business, Universitas Sumatera Utara, Medan City, class 2021 to 2022. Sample who became respondents in this study are 110 respondents. The analytical method used is multiple linear regression analysis. The results of the study show that E-WoM has a significant effect on purchase decision of Samsung Brand Mobile Phones in Undergraduate Students, Faculty of Economics and Business, Universitas Sumatera Utara, Medan City. Brand image has a significant effect on purchase decision of Samsung Brand Mobile Phones in Undergraduate Students, Faculty of Economics and Business, Universitas Sumatera Utara, Medan City. E-Trust has no significant effect as a moderator of E-WoM on purchase decision of Samsung Brand Mobile Phones in Undergraduate Students, Faculty of Economics and Business, Universitas Sumatera Utara, Medan City. E-Trust has a significant effect as a moderator of brand image on purchase decision of Samsung Brand Mobile Phones in Undergraduate Students, Faculty of Economics and Business, Universitas Sumatera Utara, Medan City. Keywords: Electronic Word of Mouth (E-WoM), Brand Image, E-Trust, Purchase Decision