PROBLEM TO BE SOLVED: To provide a reuse treatment method for deposited sand in a stricken area by tsunami.SOLUTION: The reuse treatment method for deposited sand to treat deposited sand in a stricken area by tsunami for reuse includes: a washing process for washing the deposited sand mixed with foreign matter by tsunami with washing water; fine debris removal process for removing fine debris that is the foreign matter from slurry of the deposited sand after the washing process; a sand fraction recovery process for recovering a sand fraction from slurry after the fine fabrics removal process; and a fine-grain fraction recovery process for coagulating and recovering a fine-grain fraction contained in slurry by adding coagulant 50 whose primary content is mineral material to the slurry after the sand fraction recovery process, and recovers the sand fraction in the sand fraction recovery process and the fine-grain fraction in the fine-grain fraction recovery process.
