The focus of this book was to investigate the effects of collaborative online learning towards undergraduates' attitude and teamwork skill. The further discussion was to compare the effects of collaborative online learning between Malaysian and Indonesian students. A quasi-experimental method was applied in this study. There were 128 students from two universities were selected randomly and divided into three groups (SOC, AOC and CC). SOC and AOC served as experimental groups and CC served as control group. The result showed that the students in SOC group of both countries significantly outperformed in their self regulation and teamwork mean score. However, the Indonesian AOC group also outperformed in self regulation and teamwork mean score compared to CC; whereas Malaysian AOC group did not show better result in teamwork skill than Malaysian CC group. A follow-up interview had been carried out among nine students. The qualitative responses also showed the positive results. Overall, these findings support the positive effect of collaborative online learning.