According to one implementation, a preform shaping method for producing a preform having a web, a flange, and a chamfered portion includes: pressing a first portion of a laminated body of fiber sheets by sandwiching the first portion between a first mold and a second mold; and pressing a second portion of the laminated body of the fiber sheets after pressing the first portion. The first portion corresponds to the web. The second portion corresponds to the flange. The first mold fits a surface in one side of the web, an inner surface of the chamfered portion and a surface in one side of the flange. The second mold fits a surface in the other side of the web. The second portion is pressed by sandwiching the second portion between the first mold and a third mold.