E-commerce has become an integral part of people's daily lives due to the extensive use of the Internet. Moreover, customers' positive emotions are the good feelings that a person has because of their mood or good circumstances. These can include happiness, love, liking, pleasure, or joy. This study proposes to provide an analytical framework that includes factors (sales promotion, hedonic shopping motivation, and personalization) that affect positive emotions, which in turn affects the customers' intentions to make purchases and their actual behavior within the context of e-commerce platforms. This study used the cognitive emotion theory and emotion-action tendency connection as a theoretical framework. Convenience sampling was used in an online survey to collect data from 294 clients. The findings discovered that consumers' positive emotions in e-commerce platforms in Vietnam were affected favorably by key factors such as sales promotion (β = 0.502), hedonic shopping motivation (β = 0.217), and personalization (β = 0.207). Out of these factors, sales promotion (β = 0.502) was found to have the most favorable impact on customers' pleasant feelings. In the same way, customers' pleasant emotions (β = 0.758) had a strong positive influence on their inclination to shop. Furthermore, their shopping intention (β = 0.822) also had a considerable positive influence on their behavior. The study's results may help online retailers fully understand the determinants that affect customers' pleasant feelings, shopping intentions, and behavior. With this knowledge, online stores will be able to improve how they sell products.