This research aimed to study the using of online social media in the Echo Aviation Tutorial School Thailand, and to assess the opinion of students, about using online social media in this school. Purposive sampling was employed.The participants were Executive School Director and the twenty students, who enrolled in English for Communication.There were two research instruments in this study: 1) the structured interview form, and 2) the opinion assessment form.The content validity was examined by three experts in the area of educational studies. The IOC value was between 0.67 -1.00. The data analysis was divided into two parts: 1) qualitative data were analyzed by content analysis, and 2) quantitative data were analyzed by arithmetic mean and standard deviation. The results were shown as follows:1) The benefits of using online social media in this school were revealed in three aspects: 1.1) it was used for notifying the school information conveniently, rapidly, and saved cost for school administration, 1.2) it can promote the students' class participation in real time continually, and 1.3) it increased the students' learning achievement scores by their potential.2) The assessment of students' opinion was in the high level (x ̅ = 4.29, SD = 0.65).There were two recommendations of this study. The school ought to explain the using of all functions in online social media to students in more details and compare the using of online social media proper with the school for instruction.