The 1994 national census reported a total population for this woreda of 93,895, of whom 47,201 were men and 46,694 women; 14,575 or 15.52% of its population were urban dwellers at the time. The two largest ethnic groups reported in Merti were the Oromo (71.29%), and the Amhara (26.3%); all other ethnic groups made up 2.41% of the population. Oromiffa was spoken as a first language by 65.38%, and 33.79% spoke Amharic; the remaining 0.83% spoke all other primary languages reported. The majority of the inhabitants were Muslim, with 59.71% of the population having reported they practiced that belief, while 39.91% of the population said they professed Ethiopian Orthodox Christianity.