To provide a method for manufacturing a large-size integral forming jointless bathtub made of ceramic whiteware which is not obtained in a manufacturing method of a conventional ceramic whiteware article.

A nonliquid pastelike body raw material 22 of ceramic whiteware contains a coarse grain filler of 1-3mm particle size in a range within 30-60wt.% and its water content is regulated to 9-19%. The nonliquid pastelike body raw material 22 of ceramic whiteware is used as the body material of ceramic whiteware and force-injected into the molding cavity 36 of a molding die 26 having water absorption power from an injection port 38 in pressurization and filled in the molding cavity 36. Thereafter, while maintaining the pressurization state, water absorption through the molding die 26 is performed and the body raw material 22 of ceramic whiteware is molded and operated into a large-size integral bathtub shape. Thereafter, a molded form is mold- released and burned to obtain the large-size integral forming bathtub made of ceramic whiteware.