The 1994 national census reported a total population for this woreda of 137,228, of whom 67,534 were men and 69,694 women; 23,512 or 17.13% of its population were urban dwellers at the time. The four largest ethnic groups reported in Arsi Negele were the Oromo (85.92%), the Amhara (7.69%), the Kambaata (2.73%), and the Soddo Gurage (1.08%); all other ethnic groups made up 2.58% of the population. Oromiffa was spoken as a first language by 83.65%, 11.89% spoke Amharic, and 2.44% spoke Kambaata; the remaining 2.02% spoke all other primary languages reported. The majority of the inhabitants were Moslem, with 70.94% of the population reporting they practiced that belief, while 22.29% of the population said they were Ethiopian Orthodox Christianity, and 5.34% were Protestant.