Construction by-products (remaining soil from construction) generated during the construction of new structures and the use of facilities are being used, but at present they are not sufficient. Delivering sediment deposited on a dam requires cost and time. Therefore, the method of utilizing the sediment deposited on the dam will be examined. However, the sediment deposited on the dam is brittle, it cannot be used for coarse aggregate. Therefore, the application to fine aggregate for use in mortar is examined. Mortar is affected by frost damage. This study evaluates the freeze thaw resistance of mortar using sediment deposited on dam by compressive strength and relative dynamic elastic modulus.