To provide a crucible protective sheet which improves workability by preventing damage and inclination of an internal crucible and can prevent deterioration of product quality by maintaining heat conductivity to such a degree that heat is conducted uniformly to the internal crucible from the external crucible even if compressibility is high.

The crucible 1 comprises an internal crucible 2, an external crucible 3, and a sheet 4 composed of exfoliated graphite which is disposed between the crucibles 2 and 3. The sheet has heat conductivity in the plane direction of 120 W/(mK) or more and compressibility of 20% or more when compressed with pressure of 34.3 MPa in the thickness direction.