AbstrakPenelitian ini menelaah struktur fonotaktik fonem di dalam deret vokal dan deret konsonan bahasa Tunjung (Tonyooi). Metode yang digunakan dalam penelitian ini adalah metode deskriptif kualitatif. Berdasarkan data yang diperoleh pada struktur fonotaktik fonem di dalam deret vokal bahasa Tunjung (Tonyooi) ditemukan 20 jenis deret vokal, yaitu /a.u/, /a.o/, /a.e/, /a.i/, /i.a/, /i.u/, /i.i/, /i.e/, /i.o/, /u.o/, /u.e/, /u.a/, /u.i/, /e.o/, /e.a/, /e.u/, /o,u/, /o.i/, /o.a/, dan /o.e/. Deret vokal dalam bahasa Tunjung (Tonyooi) dapat ditemukan pada posisi awal, tengah, dan akhir sebuah kata. Adapun deret konsonan dalam bahasa Tunjung (Tonyooi) ditemukan pada posisi awal, tengah, dan akhir. Bunyi-bunyi konsonan yang berderet, yaitu /h.t/, /k.b/, /k.k/, /kng.g/, /l.d/, /l.g/, /m.b/, /m.k/, /m.p/, /n.c/, /n.d/, /n.j/, /n.s/, /n.t/, /ng.k/, /r.b/, /r.c/, /r.d/, /r.j/, /r.k/, /r.m/, /r.ng/, /r.p/, /r.s/, /r.t/, /r.w/, /s.b/, /s.k/, /s.l/, /s.p/, /t.r/. Kata kunci: deret vokal, deret konsonan, dan bahasa Tunjung (Tonyooi) AbstractThis study examines the phonotactic structure of phonemes in the vowel and consonant series of Tunjung (Tonyooi) language. The method used in this study is a qualitative descriptive method. Based on the data obtained on the phonotactic structure of the phonemes in the Tunjung (Tonyooi) language vowel series, 20 types of vowel series were found, namely/au/, /ao/, /ae/, /ai/, /ia/, /iu/, /ii/, /ie/, /io/, /uo/, /ue/, /ua/, /ui /, /eo/, /ea/, /eu/, /o,u/, /oi/, /oa/, and /oe/. Vowel series in Tunjung language (Tonyooi) can be found at the beginning, middle, and end of a word. The consonant series in the Tunjung language (Tonyooi) are found in the initial, middle, and final positions. Consonant sounds that line up, namely /ht/, /kb/, /kk/, /kng.g/, /ld/, /lg/, /mb/, /mk/, /mp/, /nc/, /nd/, /nj/, /ns/, /nt/, /ng.k/, /rb/, /rc/, /rd/, /rj/, /rk/, /rm/, /r.ng /, /rp/, /rs/, /rt/, /rw/, /sb/, /sk/, /sl/, /sp/, /tr/. Keywords: vowel series, consonant series, and Tunjung language (Tonyooi)