To provide a wooden mattress structure very stabilized for the current of a river and well familiarized with the natural environment.

A plurality of logs are built on sill stones 3 arranged at specific intervals, and the sill stones 3 and logs 4 are connected with anchor metal fixtures 5 to form wooden enclosed frames 1. The wooden enclosed frames 1 pile 2-3 stages up, and the pedestals 3 of both up and down wooden enclosed frames 1 are connected with anchor metal fixture 5. The insides of the wooden enclosed frames 1 are filled with filling stones 2 respectively. Specially, natural stones are used for the sill stones 3.