A novel method for two-dimensionally arraying ferritin on a substrate is provided which obviates the need for a metal ion that permits linking between adjacent two ferritin particles. In a method of two-dimensionally arraying ferritin on a substrate, the surface of the substrate is hydrophilic, and the method includes the steps of: developing a solution containing a solvent and the ferritin on the substrate; and removing the solvent from the solution developed on the substrate, while the ferritin has an amino acid sequence set out in SEQ ID NO: 1 modified at its N-terminus.