Meidensha Corporation (株式会社明電舎, Kabushiki Kaisha Meidensha) is a Japanese, Tokyo-based company, engaged in the manufacturing and selling of water treatment equipment, electronic equipment, and information equipment. It is listed on the Tokyo Stock Exchange and is a constituent of the Nikkei 225. The company was established by Hosui Shigemune for the manufacture of electric motors in Kyobashi, Tokyo.