This study explored device ownership and accessibility, and perceptions of Thai university students toward online teaching and learning of a foundation English course during the COVID-19 pandemic. Five hundred and fifty-two university students were randomly selected to complete an online questionnaire, and 20 were randomly selected to participate in semi-structured interviews. The findings of both quantitative and qualitative data analysis are that most university students in the study own a smartphone and iPad with Internet access that enabled them to study the online foundation English course. Students' perceptions towards online classroom engagement and interaction, online lesson tasks and activities, online classroom instructional media, online English skills development, and other related issues were identified. Additionally, recommendations for instructors' use of online tools as well as the redesign of online classroom learning tasks and activities using various instructional media are given.