Purpose: The study aims to seek the factors affecting perceived online learning enjoyment among university students across Viet Nam. Design/methodology/approach: Based on the concept of the technology acceptance model (TAM), this research adopts structural equation modelling (SEM) to analyse data collected from 795 undergraduate students who have gained the experience of online courses in the period of the COVID-19 pandemic. Findings: The results of this study indicate that both perceived ease of use and perceived usefulness are significant predictors of students' perceived enjoyment in online courses while perceived obstacles are not its direct antecedents. The correlation between perceived ease of use and perceived usefulness is also affirmed in this study. Besides, differences are found based on students' characteristics including gender, grade and academic major. Research limitations/implications: As online learning turns education to be learner-centred, it is crucial to have a better understanding of students' perceptions toward this advanced learning method. The insights found in this research may be of interest to educational administrators, aimed at achieving the digital transformation success in education which may adapt to the current trend of Industrial Revolution 4.0. Originality/value: According to the best of the knowledge, this research is the first to explore the effect of the group of three predictors including perceived ease of use, perceived usefulness and perceived obstacles on the students' learning enjoyment toward the online learning method, especially in the context of Viet Nam.