PURPOSE: To form a sheet without generating any wrinkle or crack by slidably forming the periphery part of the sheet with an active part under a blank holder, compensating an excessive part in a part wherein completed parts exist and simultaneously pressurizing a central slide against the sheet.

CONSTITUTION: The sheet (blank) 7 to be formed is placed on a supporting device 4, the blank holder 1 is applied to the peripheral part of the sheet 7, and the central slide 2 is applied to the central part of the sheet 7. Thereupon, the peripheral part of the sheet 7 is slidably formed by at least one active part 11 under the blank holder, and the excessive part having an initial sheet thickness is compensated to a volume which is formed in the part wherein the completed parts exist. The central slide 2 is moved simultaneously with it, the sheet 7 is pressurized against the surface of the central part in the supporting device 4, and a bending part of the central part in the sheet 7 is formed. This method is applicable to the press-bending of a thick plate as well.