Objectives: Text reading fluency is an important skill for students using Korean which has a transparent orthography system. This study longitudinally observed text reading fluency in Korean first-grade students with and without dyslexia over 3 semesters. Methods: Forty children with dyslexia and forty typically developing children participated in the study. They were grouped based on their performance at the beginning of the second grade. All students exhibited normal levels of listening comprehension and nonverbal intelligence. Over the three semesters, participants read six texts at various decoding levels. We then analyzed the number of correctly read syllables per 10 seconds, text reading accuracy, and speed. Results: Both the dyslexia and typically developing group showed significant differences in the number of syllables read per 10 seconds at all time points. Text reading accuracy improved significantly from first to second semester of first grade for both the dyslexia and typically developing group. By first semester of second grade, students with dyslexia achieved approximately 80% accuracy. While dyslexic students’ reading speed significantly improved from second semester of first grade to the first semester of second grade, they remained slower than typically developing students. Typically developing students showed consistent improvements in reading speed across all time points. Conclusion: When intervening with lower-grade students with dyslexia in Korea, it’s crucial to conduct not only decoding but also text-level fluency activities. Providing individualized texts that are decodable for dyslexic children seems to be essential.