The small-scale food and beverage (F&B) businesses have undergone considerable growth in recent years in Vietnam. The objectives of this study are to test the impact of social media marketing on purchase intention in this industry and outline ways to promote small-scale F&B businesses. In specific, media marketing activities such as online advertising, electronic word-of-mouth (e-WOM) aspects, i.e., recommendations, and reviews were measured. In addition, the role of trust as a mediating factor was also studied in the relationship between those online marketing activities and purchase intention. To have a better insight into the study, primary data were collected from an online quantitative survey with 243 valid samples from Binh Duong Province, Vietnam. The data were then analyzed by the multiple regression analysis to ensure the significance of the interrelationship between variables. Next, the bootstrapping method was deployed to examine the mediating impact of trust in the framework. The findings showed that online advertising did not influence purchase intention while the other two e-WOM elements showed a significant direct relationship with the dependent variable, in which recommendations saw the greatest effect. As for the mediation of trust, it revealed the significant impact of recommendations on purchase intention while reviews and online advertising respectively contributed to purchase intention with lower values.