A method for efficiently separating and recovering rare earth in waste CRT phosphor under mild conditions belongs to the field of rare earth resource recovery. The method comprises the following steps: mechanically activating the waste CRT phosphor through ball milling; performing pressurized leaching on the activated CRT phosphor waste under a catalytic oxidation condition with low concentrationsulfuric acid and hydrogen peroxide as a leaching agent to obtain a rare earth element-containing mixed leachate; enriching and recovering rare earths yttrium and europium through a two-step precipitation process, and performing secondary extraction by using low concentration hydrochloric acid to obtain a rare earth leachate; and efficiently separating and recovering europium and yttrium through aphotochemical process combined chemical precipitation technology. Extraction of the rare earth elements is rapidly completed by the low concentration acid solution, and the rare earths are directly efficiently separated and recovered through the two-step precipitation process and the photochemical process in the subsequent process, so the secondary pollution problem of pollution of H2S gas generated during direct strong leaching to the environment is effectively prevented, the resource utilization rate of the whole process flow is high, and harms of the waste processing process to the body health of workers are reduced as possible.