A method for the treatment of radioactive wastes from nuclear power plants reactors that have water under pressure and boron adjustment of reactivity, comprising the steps of: A) separately collecting of: (i) an acidic radioactive waste having a pH of less than 5.5, free of boron salts; and (ii) an alkali radioactive waste having a pH greater than 5.5, containing boron salts; thereafter B) separately concentrating of the acidic- and the alkali liquid radioactive wastes; that is characterized in that C) the alkali radioactive wastes are concentrated until their concentration of boron acid reaches from 35 to 200 g/l; and D) the acidic radioactive wastes, free of boron acid, are concentrated until reaching a total salt content of 400 g/l to 500 g/l; after that E) the concentrates from C) and D) are mixed in a mixing ratio from 0.5:1 to 1:2, based on recalculation of gram-equivalent ratio of sodium hydroxide towards boron acid into the radioactive wastes, which results in a mixture with a pH from 8.0 to 10.1 and realization of a process of separation of borax; followed by parallel implemented, on the one side F) filtration, subsequent washing, re-crystallization and separation of borax crystal mass with level of radiation safe for the environment; and on the other side G) separation of a filtrate containing 20-25 g/l of boron acid, from which (i) one part is mixed with salts of alkaline-earth metals, resulting in a formation and separation of insoluble alkaline earth metal borates with level of radiation safe for the environment, as well as a liquid radioactive waste containing from 2 to 4 g/l boron acid; and (ii) the other part of the filtrate, containing 20-25 g/l boron acid and/or solution of borax with the same content of boric acid is processed by means of electrodialysis until a sodium hydroxide solution with concentration up to 150 g/l and a boron acid solution with concentration up to 60 g/l are obtained. A) separately collecting of: (i) an acidic radioactive waste having a pH of less than 5.5, free of boron salts; and (ii) an alkali radioactive waste having a pH greater than 5.5, containing boron salts; thereafter (i) an acidic radioactive waste having a pH of less than 5.5, free of boron salts; and (ii) an alkali radioactive waste having a pH greater than 5.5, containing boron salts; thereafter B) separately concentrating of the acidic- and the alkali liquid radioactive wastes; C) the alkali radioactive wastes are concentrated until their concentration of boron acid reaches from 35 to 200 g/l; and D) the acidic radioactive wastes, free of boron acid, are concentrated until reaching a total salt content of 400 g/l to 500 g/l; after that E) the concentrates from C) and D) are mixed in a mixing ratio from 0.5:1 to 1:2, based on recalculation of gram-equivalent ratio of sodium hydroxide towards boron acid into the radioactive wastes, which results in a mixture with a pH from 8.0 to 10.1 and realization of a process of separation of borax; followed by parallel implemented, on the one side F) filtration, subsequent washing, re-crystallization and separation of borax crystal mass with level of radiation safe for the environment; and on the other side G) separation of a filtrate containing 20-25 g/l of boron acid, from which (i) one part is mixed with salts of alkaline-earth metals, resulting in a formation and separation of insoluble alkaline earth metal borates with level of radiation safe for the environment, as well as a liquid radioactive waste containing from 2 to 4 g/l boron acid; and (ii) the other part of the filtrate, containing 20-25 g/l boron acid and/or solution of borax with the same content of boric acid is processed by means of electrodialysis until a sodium hydroxide solution with concentration up to 150 g/l and a boron acid solution with concentration up to 60 g/l are obtained. (i) one part is mixed with salts of alkaline-earth metals, resulting in a formation and separation of insoluble alkaline earth metal borates with level of radiation safe for the environment, as well as a liquid radioactive waste containing from 2 to 4 g/l boron acid; and (ii) the other part of the filtrate, containing 20-25 g/l boron acid and/or solution of borax with the same content of boric acid is processed by means of electrodialysis until a sodium hydroxide solution with concentration up to 150 g/l and a boron acid solution with concentration up to 60 g/l are obtained.