This study examines the factors affecting online learning outcomes of university students in Dong Nai, Vietnam in the context of the Covid-19 pandemic. Applying quantitative research methods, surveying 300 students from universities in the province. The results of multivariate regression analysis identified five main factors affecting online learning outcomes, including: learning persistence, learning methods, learning motivation, interaction with lecturers and facilities. Of which, learning persistence has the strongest impact. Based on these results, the study proposes solutions to improve online learning effectiveness, focusing on developing self-study skills, improving teaching methods, enhancing learning motivation and interaction between lecturers and students. The study provides an important basis for policy making and investment in online higher education in Vietnam.