Module structure and plant construction method

A plant construction method comprising:

• forming a module structure within a movable range of a crane from an arranging location of a facility device component, the module structure including a support member which temporarily supports the facility device component to be arranged in a cell constituting a plant at a designed position and a frame which fixes the support member;
• carrying the module structure into the cell at the arranging location of the facility device component with the crane after a floor face of the cell is constructed;
• forming a wall face or a ceiling face of the cell in parallel to attaching of the facility device component into the cell;
• and
• removing by disassembling the frame or the support member in the module structure after forming the wall face or the ceiling face.