The invention discloses a hydrocracking tail oil ultra-deep adsorbent desulfurizing and denitrifying method, wherein, hydrocracking tail oil with a certain content of sulphide and nitride is contacted with a hydrocracking tail oil ultra-deep adsorbent desulfurizing and denitrifying absorbent at certain temperature, pressure and airspeed, thereby obtaining desulfurized and denitrified hydrocracking tail oil which is absorbed and refined. The refined hydrocracking tail oil has a sulfur content lower than 10mug.g<-1> and a nitrogen content lower than 2mug.g<-1>, which satisfies requirements of hydroisomerized dewaxing material. The hydrocracking tail oil ultra-deep adsorbent desulfurizing and denitrifying method employs tower-type continuous operation of fixe bed, the process is simple and easy to realize, thereby overcoming disadvantages of the prior art that mixing and separating of liquid denitrifier and oil product is difficult, desulfurizing and denitrifying depths are insufficient, and operation is complex. Therefore, the method is especially applicable to ultra-deep adsorbent desulfurizing and denitrifying of hydrocracking tail oil.