Bioethanol production using sugarcane as a raw material is effective in reducing greenhouse gas emissions but may be problematic in competing for the raw material for sugar production. A simulation in an earlier study demonstrated that sugar and ethanol production can be both increased by simultaneously introducing two technologies, high yielding sugarcane varieties and sugar/ethanol combined production process, into a sugar mill. However, in order to introduce these technologies to a sugar mill, it is necessary to acquire data through a plant-scale demonstration. In this study, we conducted demonstration tests from sugarcane cultivation to sugar/ethanol combined production on a pilot scale on the island of Ie, Okinawa Prefecture, and obtained material balance data when seven types of sugarcane were used as raw materials. In addition, we clarified the effect of sugarcane ingredient composition on each process and demonstrated that simultaneous increase in production of sugar and ethanol can be achieved.