Radioactive waste liquid treatment method and system

The embodiment of the invention discloses a radioactive waste liquid treatment method. The method comprises the following steps: feeding radioactive waste liquid into an evaporator, circulating the radioactive waste liquid between a heating device and a separating device, heating the radioactive waste liquid by the heating device so as to boil the radioactive waste liquid, and carrying out vapor-liquid separation on the boiled radioactive waste liquid in the separating device to generate secondary vapor; secondary steam generated by evaporation of the radioactive waste liquid is introduced into the steam compression device, and after the steam compression device is used for compressing and heating the secondary steam, the secondary steam is conveyed to the heating device to serve as a first heat source of the heating device to exchange heat with the radioactive waste liquid; discharging raffinate formed after the radioactive waste liquid in the evaporator is concentrated; wherein in the evaporation process of