Purpose: The purpose of this study was to understand and describe the experiences of nurses in charge of COVID-19 screening at general hospitals in South Korea. Methods: Data were collected through individual in-depth interviews with 14 nurses who had been working for more than a month at a screening clinic operated by two general hospitals from May 11 to July 20, 2021. Verbatim transcripts were analyzed using Colaizzi’s phenomenological analysis. Results: As a result of analysis, four theme clusters were extracted from nurses’ experiences, as follow: the role of the hospital gatekeeper entrusted with managing the COVID-19 pandemic, struggling to maintain the protective barrier, boundlessness like a Mobius strip, and driving force to endure as a nurse in charge of COVID-19 screening. Conclusion: The results of this study provide a deeper understanding of the lives of screening clinic nurses who are struggling with the COVID-19 situation. The results are expected to be useful in providing basic data for improving the infection control system and response strategies that can be applied to nursing practice in other pandemic situations.