A paper-based, origami, glucose/O-2, biofuel cell (PBFC) was constructed as an array of two individual cells by screen-printing. The fabricated PBFC, which modulated output voltage by paper folding, exhibited almost 1V of open-circuit voltage without any booster circuit. The maximum output power density of the PBFC was 180 mu W cm(-2). This PBFC concept is highly applicable to the development of high-power, low-cost, and flexible energy-harvesting devices.