The 2007 national census reported a total population for this woreda of 45,523, of whom 23,386 were men and 22,137 were women; 6,531 or 14.35% of its population were urban dwellers. The majority of the inhabitants said they practised Ethiopian Orthodox Christianity, with 67.37% of the population reporting they observed this belief, while 10.16% of the population were Protestant, 12.68% practiced traditional beliefs, and 9.68% were Moslem. Based on figures from the Central Statistical Agency in 2005, this woreda has an estimated total population of 29,288, of whom 14,654 are men and 14,634 are women; 5,615 or 19.2% of the population are urban dwellers, which is greater thanthe Zone average of 10.7%. With an estimated area of 2,857.97 square kilometers, Bulen has a population density of 10.2 people per square kilometer which is greater than the Zone average of 8.57. The 1994 national census reported a total population for this woreda of 21,111 in 4,295 households, of whom 10,624 were men and 10,487 were women; 3,264 or 15.46% of its population were urban dwellers. The five largest ethnic groups reported in Bulen were the Shinasha, the Gumuz, the Amhara, the Oromo, and the Awi a subgroup of the Agaw; all other ethnic groups made up 0.2% of the population. Boro is spoken as a first language by 45% of the inhabitants, 33.4% speak Gumuz, 11% Oromiffa, and 10% speak Amharic; the remaining 0.6% spoke all other primary languages reported. The majority of the inhabitants said they practiced Ethiopian Orthodox Christianity, with 65% reporting that as their religion, while, 21.5% observed traditional religions, and 9.8% were Muslim. Concerning education, 15.1% of the population were considered literate, which is less than the Zone average of 18.61%; 9.38% of children aged 7–12 were in primary school; 0.1% of the children aged 13–14 were in junior secondary school; and 0.85% of the inhabitants aged 15–18 were in senior secondary school. Concerning sanitary conditions, 12.6% of the urban houses and 3.6% of all houses had access to safe drinking water at the time of the census; 41.2% of the urban and 9.8% of the total had toilet facilities.
