In the age of information explosion, people are increasingly accustomed to acquiring knowledge during fragmented periods of time, which has contributed to the growing popularity of micro-learning. However, when micro-learning takes place in non-formal or informal settings, it can be easily disrupted and may lack interaction, negatively impacting the learning experience and knowledge acquisition. This study examined the effect of learning communities on knowledge acquisition and learning experience in non-formal micro-learning settings. An 8-module micro-learning course was designed, and 80 participants were divided into an experimental group with a learning community and a control group without one. All participants completed a pre-test and post-test. The results showed significant improvements in post-test scores for both groups, with no notable difference in knowledge acquisition between them. Learners who took notes and repeatedly reviewed the learning content tended to have higher post-test scores. In addition, differences between the groups in terms of mental effort and satisfaction were insignificant. By the end of the course, the control group expressed a stronger desire to join a learning community. Community learners who made significant progress reported enjoying learning within the community, while those who did not regularly check community messages and experienced a decrease in test scores reported that excessive messaging caused distress. These findings have implications for course designers and researchers aiming to enhance micro-learning through online learning communities.