A soil kneader in which bending occurring in the direction of extrusion of a soil flow pattern and causing a molding failure is suppressed as much as possible and which provides a columnar body having highly uniform quality and suitable for use in molding a honeycomb structure etc. The soil kneader (30) has a supply opening (19) from which soil enters the inside of the kneader, a rotating shaft (6), a helical rotating blade (5) provided along the rotating shaft (6), and a drum (2) including a screw (4) for kneading the soil and also including an extrusion opening (20) from which the soil is extruded in a columnar shape. The drum (2) has a pressure raising section (10) on the supply opening (19) side, an extrusion section (12) having a smaller diameter than the pressure raising section (10) and provided on the extrusion opening (20) side, and a flow regularizing section (11) located between the pressure raising section (10) and the extrusion section (12). In the flow regularizing section (11), the diameter of the rotating shaft (6) is gradually reduced toward the extrusion opening (20). A rotating shaft end section (7) is located about the boundary between the flow regularizing section (11) and the extrusion section (12).