The Elephant Action League, which fights wildlife crime, said he ran an ivory trafficking network across five African countries: Tanzania, Burundi, Zambia, Mozambique and southern Kenya.He was sentenced alongside his brothers, Lucas Mathayo Maliango and Abdallah Ally Chaoga.
The three were arrested in October 2015 while attempting to smuggle tusks worth more than $850,000 (£700,000).
Maliango was accused of supplying ivory to Chinese citizen Yang Fenglan, known as the "Ivory Queen", who is on trial in Tanzania for trafficking more than 700 elephant tusks worth $2.5m (£1.7m).
Conservationists have said demand for ivory in China has fuelled poaching.
Although there is an international ban on buying and selling ivory across borders, it is allowed inside certain countries.