[en] A benchmark physics experiment of a metallic-fueled LMFBR was performed at Japan Atomic Energy Research Institute's Fast Critical Assembly (FCA) in order to examine availability of data and method for a design of metallic-fueled core. The nuclear data and the calculation methods used for a LMFBR core design have been improved based on the oxide fuel core experiments. A metallic-fueled core has a harder neutron spectrum than an oxide-fueled core and has typical nuclear characteristics affected by the neutron spectrum. In this study, availability of the conventional calculation method for the design of the metallic-fueled core was examined by comparing the calculation values of the nuclear characteristics with the measured values. The experimental core (FCA assembly XVI-1) was selected by referring to the conceptual design of Central Research Institute of Electric Power Industry. The calculated-to-experiment (C/E) value for k_eff of assembly XVI-1 was 1.001. From this, as far as the criticality the prediction accuracy of the conventional calculation for the metallic-fueled core was concluded to be similar to that of an oxide-fueled core. (author)