This paper aims to investigate Korean EFL learners’ pragmatic performance in request speech acts in comparison with native speakers of English. Written discourse completion tasks (WDCT) are used to examine how native and non-native speakers request in terms of request strategies, internal modifications, and external modifications. The results show that first, Korean learners had a higher frequency of inappropriate strategies than native speakers. Second, they lacked the quantity and variety of internal modifications both lexically and syntactically. However, regarding external modifications, their use of supportive moves was similar to that of natives in frequency and order. In addition, this study identified newly emergent supportive moves that are Korean-specific and detrimental to communication goals. The findings shed light on pragmatic instruction in the Korean EFL situation by providing research-informed data. Several pedagogical implications are suggested for application in teaching.