Author Affiliations 1Institute of Frontier Science and Technology, Okayama University of Science, Japan 2Faculty of Software and Information Technology, Aomori University, Japan 3Department of Mechanical Engineering, National Institute of Technology, Akashi College, Japan 4Cell Function Lab., Graduate School of Science, Osaka City University, Japan 5Research Institute for Electronic Science, Hokkaido University, Japan Received: October 10, 2020 | Published: October 22, 2020 Corresponding author: Syou MAKI, Institute of Frontier Science and Technology, Okayama University of Science 1-1 Ridai-cho, Kita-ku, Okayama, 700-0005 Japan DOI: 10.26717/BJSTR.2020.31.005090 We measured the thermal conductivity (λ ) and thermal diffusivity (α ) of a myxomycete (slime mold) by the transient short-hot wire method. The measurements were conducted two times with temperatures varying from 277 to 300 K. In the results, λ = 0.489-0.572 (W/m ⋅ K), and α = 8.36×10-8-2.48×10-7 (m2/s). The thermal properties of slime molds are close to those of water. In particular, the λ is similar to that of biological materials (cells, human blood and plasma), and slightly different from that of some kinds of organic materials (lysozyme crystals, wheat, apple, and tomato), and evidently different from inorganic substances (sand and soil). Keywords: Transient Short-Hot Wire Method; Myxomycetes; Biological Materials; Thermal Property