Construction of Closed Ecology Experiment Facilities (CEEF) is started in Rokkasho village of Aomori prefecture, the northern part of Honshu island in Japan. CEEF consist of Closed Plant Experiment Facility (CPEF) and Closed Geo-Hydrosphere Experiment Facility (CGEF) with capability to simulate ecological systems containing plants, animals, human, trees and sea living things. These biospecies are selected according to experimental plans and are maintained their lives in controlled environments. Recyclings of materials circulating in the closed system of CEEF are made mainly utilizing physical chemical treatments.The construction of CEEF will be completed by 1998. This paper mainly describes design of CPEF.