Abstract: Korebaju [kòrèβáh ] (ISO 639-3: coe) is a Western Tukanoan language from the South-Western part of Colombia.A study conducted in 2017 and 2018 with six native speakers (3 female and 3 male) shows that Korebaju has an inventory of 17 consonants /p, t, k, pʰ, tʰ, kʰ, β, ɸ , s , h, t ͡ ʃ, m, n, ɲ, ʰm, ʰŋ, r/ and 6 oral vowels /i, e, a, o, u, ɨ/, 6 nasal vowels /ĩ, ẽ, ã, õ, ũ, ̃/ and 3 glottal vowels /aˀ, eˀ, oˀ/.Contrary to previous studies, this paper shows that Korebaju does not include the vowel [ɯ] in its phonemic inventory.The vowel [ɯ] is an allophone of the high back vowel /u/ when it follows a palatal consonant.In the same context, the high central vowel /ɨ/ also has an allophone [ɪ].This paper focuses on an acoustic and articulatory description.Data come from a set of words recorded with synchronized audio and EGG signals.