This study examined the comprehension of native speakers and English-speaking second language learners of OSV word order with case markers using a "matching sentences to movies" method. Based on the Shallow Structure Hypothesis and previous research in other free word order language, this study hypothesized that 1) Korean OSV word order might be difficult to process for beginning English L2 learners of Korean due to L1 word order (SOV) or First Noun Principle. 2) Intermediate English -- speaking L2 learners of Korean will use case markers as cues to identify grammatical relations in sentence comprehension as well as native speakers regardless of the L1 similarity (L1 word order and presence/absence of case markers). Ten native speakers, ten English beginning-level learners, and ten English intermediate-level learners participated in the study. The test sentence types were 1) SOV word order with subject and object markers, 2) SOV word order with subject markers, 3) OSV word order with subject and object markers, and 4) OSV word order with subject markers. The result demonstrated that intermediate L2 learners were able to comprehend OSV word order with case markers similar to those used by native speakers when they identify agent/patient roles in Korean. These findings indicate that 1) English L2 learners are able to understand OSV word order with case markers using native-like processing strategy (use of case markers as cues) regardless of their L1, and 2) Native-like comprehension of OSV with case markers is attainable with intermediate proficiency.