The background of this research was based on the lack of adequate research results to describe bound vowel graphemes in the Balinese script writing system with all its complexities. The purpose of this research was to decipher bound vowel graphemes and their behavior in a writing system based on Balinese script. The research method applied in this research was a qualitative descriptive method. The qualitative data source was in a graphic form of dependent vocal grapheme and its representation in Balinese, which is included in the list of Balinese scripted entries in Bali-Indonesian Latin and Balinese Dictionary II Edition. The data were collected through the document analysis technique and then analyzed by describing the new meaning and appearance, determining the frequency of the occurrences, and grouping them based on grapheme definitions that apply across writing systems. The results showed that the form of the vowel graphemes in Balinese script differed in the initial and bound positions. For the vowel graphemes in the bound position, the size was smaller than the main and consonant graphemes and they were rather dependent, which were dependent on them. For example: vowels above the main consonant grapheme such as for /i/ and <)> for /ђ/; vowel under the main consonant grapheme such as for /u/, on the left of the main consonant grapheme such as for /e/, and the combination of two basic shapes that did not appear next to each other (not continua) such as for /o/. Vowel graphemes in the Balinese script for /i/, /ђ/, and /u/ did not occupy their own segmental spaces horizontally, which reflected that these graphemes were bound graphemes because they could not arise alone. Likewise, the vowel graphemes displayed on the horizontal axis for /e/ and /o/ were subsegmental graphematic and usually obligatory bound.