PROBLEM TO BE SOLVED: To provide a plant cultivation device, and to provide a method for producing an objective protein in genetically altered tomato. SOLUTION: The plant cultivation device includes in a laminated structure a plurality of cultivation chambers having a light environment adjusting means for adjusting a light environment to plants, an exhaust means for adjusting heat from the light environment adjusting means, a hydroponics means, and a means for adjusting the carbon dioxide concentration in indoor air. COPYRIGHT: (C)2010,JPO&INPIT