This study investigated how the use of context-based learning with multimedia tools affected second-language (L2) learners’ acquisition of Korean vocabulary. The recently developed Motion Dictionary (MD) is a video-based dictionary that searches an entire video library (e.g., TV, drama, movies) and returns every video clip related to a specified word. The MD was initially developed to provide students with relatable examples of vocabulary usage that are rich in context and culture. In this study, we focused on Chinese learners of L2 Korean who used self-regulated learning with three different multimedia variants: videos, information quantity, and meta-cognition. In regard to videos, we found that effect on vocabulary learning varied depending on whether viewers were familiar with a video or not; those who were familiar with a video displayed the characteristics of vividly remembering the scenes and lines they saw while studying, even after the end of the learning period. Next, with regard to quantity of information, all the learners who participated in the study were interested in what was provided by all the multimedia learning tools, but in some cases, it was difficult for them to focus on it. We pointed out that these problems were caused by the way information is presented rather than by the amount of information. We could also find interesting examples such as: If the learner is not provided with the relevant information, or if the information they want is not presented, the motivation for learning will rather increase, and the learners will find the dictionary. Finally, with respect to meta-cognition, we found that significant learning occurred, as well as increased learning motivation, when the background knowledge of the learners enhanced but also differed from the new information provided during the learning process. Further studies should be conducted with groups of participants with different demographics to further the discussion of self-regulated learning courses based on multimedia learning tools in Korean language education.