The invention discloses a method for preparing a high-efficiency hydrophilic modified polyethylene hollow fibrous membrane, which comprises the following steps of: (1) synthesizing polyethylene glycol-grafted modified polyethylene: melting the polyethylene at high temperature of between 280 and 320 DEG C, introducing excessive oxygen, pretreating for 1 to 2 hours, adding polyethylene glycol and an acid catalyst into the polyethylene melt, and introducing nitrogen for condensation reaction at high temperature to obtain the polyethylene glycol-grafted modified polyethylene; and (2) performing blending melt spinning: blending the polyethylene glycol-grafted modified polyethylene and polyethylene, and performing melt stretching spinning at the temperature of between 200 and 220 DEG C in a melt spinning machine to obtain the polyethylene hollow fibrous membrane. The preparation method is simple; and the prepared polyethylene hollow fibrous membrane has excellent durable hydrophily and pollution resistance. The prepared separation membrane is mainly used for filtering aqueous liquid, treating sewage, separating proteins and the like.