The purpose of this study was to determine factors of difficulties in reading Korean characters, character features and changes in size. It was to help students with low vision read effectively and enhance the reading speed and accuracy. The subjects were 20 high school students with low vision and the degree of visual impairments ranged from 0.05 to 0.2. They were given reading difficult levels to 500 characters that were most frequently occurred through the use of Korean characters frequency analysis program. First, 20 students with low vision were required to read the material and they were asked about factors that made it difficult to read them. Thus the largest number of students indicated the morphological confusion in reading characters and structural complexities stemming from multi-strokes combination of characters. The sizes and shapes of characters were indicated as elements for reading difficulties. Confusions and complexities that indicated as the most difficult reading factors showed that 65% of students indicated confusions and 35% of them, complexities. Second, for features of characters that were difficult for students with low vision to read, consonants such as ‘ㄹ, ㅂ, ㅇ’ and ‘ㅎ’ were difficult to read compared to other consonants and vowels such as ‘ㅗ, ㅡ’ and ‘ㅔ’ showed high reading difficult levels. As for the character combination method, lengthways combined characters were difficult to read and characters that were formed by close arrangements between neighboring character elements and 9 or more strokes took more time to read.