The invention discloses a liquid nitrogen ultralow temperature fluid delivery device, comprising a liquid nitrogen tank and a tank cork. Nitrogen enters metal pipes and liquid nitrogen is discharged out of the metal pipes and penetrates through the cork to enter an inner chamber of the liquid nitrogen tank, a press bar which is fixedly pressed against the upper surface of the cork is arranged between the two metal pipes, a low temperature resistant thermal insulating layer is arranged between the cork and the metal pipes. The delivery device of the invention can bear ultra low temperature of negative 196 DEG C and pressure of 0.05 MPa, so that ultra low temperature liquid can not cause damage to ordinary cork due to frost cracking to break the sealing; the device of the invention features available materials, convenient manufacture, reliable use and low cost and application of the heat insulation protection structure to other occasions relating to low temperature.