This study investigates the effect of usability on attitude and purchase intention of consumers and examines the mediating role of customer satisfaction. Based on survey data of 509 customers who have purchased from and experienced Shopee in Vietnam, Structural Equation Modelling (SEM) was used to test the research hypotheses. Research results show that ease of use, ease of understanding, ease of purchase, and ease of ordering have a positive influence on customers 'satisfaction. Ease of use, ease of understanding, and ease of ordering have a positive influence on attitudes towards purchase. Meanwhile, ease of use alone has a positive effect on purchase intention. In particular, this study shows that ease of use, ease of understanding, ease of purchase, and ease of ordering have an impact on attitude and purchase intention indirectly through consumer satisfaction.