Kaisan Note (解散ノート; Disbandment Note) is a book written by Momoko Gumi Company. It is her fifth book overall, and her third essay book. Like her previous essay books, the book details her time in BiSH, this time talking about the group's disbandment and final days of activity.
It was released at the same time as her first digital photobook, Digital Genshoku Bijozukan Nigorinagara mo, Sukitootteiru.