PURPOSE: To provide a screw conveyor heightening the efficiency of earth discharging work in the case of performing curved work by a shield construction method and enabling earth discharging work without soiling the inside of a pit even in the case of drilled earth being sludge or granular.

CONSTITUTION: A screw conveyor is provided with a cylindrical case 13 of the specified length, a driving shaft 15 disposed on the axis of the case 13 inside of the case 13, and a blade body 19 fitted spirally to the driving shaft 15 so as to transfer transferred material in the longitudinal direction of the case 13 inside of the case 13 by the rotation of the driving shaft 15. In this case, the driving shaft 15 is formed of a core member 25 divided in the longitudinal direction and provided with rigidity, and a universal joint 29 for connecting these divided core members 25 in the bendable state. The case 13 part and the blade body 19 at least near the position of the universal joint 19 are formed of flexible material.