This study conducted a case study on two fifth-grade students who had difficulties with Korean word writing. One of the students was identified as having ADHD symptoms, while the other did not. Both students were trained for three weeks to compare the intervention effects of Cover-Copy-Compare (CCC) and copy strategies on Korean word writing. The CCC strategy emphasizes the use of orthographic working memory and the self-inspection process. As a result, both CCC and copy strategies similarly facilitated word writing in the student without ADHD, while only the CCC strategy was effective in the student with ADHD. These results suggest that CCC and copy strategies are effective in improving Korean word writing among Korean elementary school students with writing difficulties. In particular, the CCC strategy is useful for students with ADHD who struggle with poor spelling. The results were discussed in comparison with those of English-speaking students.