This study examines the integration of ChatGPT into an advanced Korean course in a U.S university context, with a focus on its instructional design and classroom implementation. Over a semester, eighteen students used ChatGPT as a supplementary tool within process-oriented writing tasks. Survey data were used to examine learners’ responses to this instructional use of ChatGPT. The results indicate that students perceived ChatGPT as particularly helpful for grammatical corrections and receiving immediate feedback. Learners who recognized its benefits reported a positive impact on the usefulness of feedback, their writing development, and interest in future AI use. However, concerns about over-reliance, ethical issues, and occasional inaccuracies were also noted. By situating ChatGPT within a specific instructional context, this study highlights both the perceived benefits and limitations of AI-assisted writing in Korean language education. This study also offers practical guidance for educators, including structured stages for AI application in writing, usage guidelines, assessment criteria, and sample prompts. Finally, it emphasizes a balanced approach in which AI complements, not replaces, teacher feedback to maintain quality through professional judgment.