This study aims to extract grammatical collocation patterns from the learner corpus constructed by the National Institute of the Korean Language (2015–2019) and to investigate the usage patterns of grammatical collocations among Korean language learners. Grammatical collocations are particularly interesting because they involve two or more linguistic units that function as a single, integrated entity and because these units include forms responsible for grammatical functions. In particular, grammatical collocations are not only a challenging aspect for foreign learners of Korean but also a crucial component in language instruction. Therefore, extracting grammatical collocations from a large-scale learner corpus and analyzing their characteristics is of utmost importance. To achieve this, this study extracted grammatical collocations according to proficiency levels from a morphologically analyzed learner corpus consisting of approximately 2.6 million word tokens and examined their characteristics. Furthermore, to highlight the distinctive features of grammatical collocations in the learner corpus, a comparative analysis was conducted with a native Korean corpus. Through this analysis, the study quantitatively and qualitatively examined the usage patterns of grammatical collocations among Korean learners based on their proficiency levels, while also explicitly identifying distinctions between learners' grammatical collocations and those of native speakers.