PROBLEM TO BE SOLVED: To reduce the reduction of an oil film thickness due to positional travel of a shoe for a cell so as to operate a device safely and accurately by constituting a hydrostatic shoe into a warping shape in the reverse direction to warping deformation of a core shaft in an operation condition. SOLUTION: A position of a hydrostatic shoe 2 indicates a positional relation of the shoe 2 and a hollow roll cell 3 in a central part in the axial direction of the shoe 2 in a non-load condition, and a clearance of a shoe lubrication face 21 for an inner face of the hollow roll cell 3 is symmetrical on a shoe lubrication face out side and a shoe lubrication face in side. B position of the shoe 2 is a position in a non-load condition having warping amount δ1 in advance and the shoe 2 is positioned close to left upper side for the cell 3. A clearance between the lubrication face 21 and the inner face of the cell 3 is small on an in side when compared with an out side at B position, but the shoe 2 moves to A position and the lubrication face 21 can keep satisfactory oil film thickness between the inner face of the cell 3 and it because a core shaft 1 is deformed in right under direction in an operation condition, thereby eliminating seizure of the shoe 2.