A splint and an operation method thereof are provided. The splint includes a plurality of plates and a splint adjustment device. The splint adjustment device is connected to the plurality of plates and configured to allow the plurality of plates to move relatively close to each other or relatively away from each other. At least one of the plurality of plates comprises at least two split portions, and the at least two split portions are configured to be separated from each other or be combined with each other, so as to allow a space surrounded by the plurality of plates to be opened or closed.
