This study analyzes and compares the use of English future markers―“will” and “be going to”―by native speakers (NS) and Korean learners (NNS). The datasets were extracted from a native speaker corpus, the Corpus of Contemporary American English (COCA), and a learner corpus, the Incheon National University Learner Corpus (MULC). They were compared to identify similarities and differences in using the futures between NS and NNS. The results show that native speakers use both forms more frequently in their speech. In contrast, Korean learners tend to use―or overuse― “will” significantly in writing and “be going to” in speaking, relative to their native counterparts. However, no significant difference is observed in the frequency of use of “be going to” in writing and “will” in speaking. Pedagogical implications are also presented. (Kookmin University)