Abstract\nPhosphoric acid is used in chemical industry with about 80 % of its world total production consumed for phosphoric fertilizers, 12 % for synthetic detergents, 4 % for the animal feed additive and 4 % for food and drink additives, metal treatment and water treatment. Annual production of phosphoric acid in the world is 38 million tons, in the Europe 4 million tons. It is produced by two basic technological methods: the “wet” process and the thermal process. Today, about 85-90 % of the phosphoric acid production facilities employ the wet process because it is cheaper. \nThe aim of the present paper is to estimate the effect of the phosphate rock quality on the efficiency of the wet process phosphoric acid production by the dihydrate method. The materials and heat balances are made. The consumption coefficients for the production of wet process phosphoric acid by the dihydrate method are calculated and analyzed for phosphates of different qualities.