Olubo or Lolubo is a Central Sudanic language spoken by 33,000 Olubo people in Southern Sudan.

Phonology

Consonants

Vowels

Vowels form two vowel harmony sets, based on advanced and retracted tongue root. The [-ATR] group is, and the [+ATR] group is. is phonetically [-ATR] but is found in roots of both sets. There is a tenth vowel quality, which only occurs after. When and are in separate morphemes, is in free variation with.

Tones

Olubo has high, mid , and low tones.There are also six compound tones, low-mid , low-high , mid-low , mid-high , high-low , and high-mid.