The characteristics of L2 learners are different from each other both from the broad and narrow senses. Each learner is different from one another and shows a wide range of learning behaviors in formal and informal learning environments. This study summarizes the already-published literature based on the research in the USA, Australia, Bangladesh, Brazil, Germany, Japan, Malaysia, and Taiwan. Every individual research illustrated the varieties of characteristics of autonomous learners and, at the same time, there are some similarities in the behaviors of autonomous learners around the world. This paper tries to display the theoretical claims about the characteristics of autonomous learners and show the similarities and differences in the characteristics of L2 autonomous learners found in research around the world on L2 teaching and learning environments by answering the following research questions.