The　possibility　of　using　crushed　oyster　shell　to　partly　replace　the　fine　aggregate　of　concrete　was　evaluated.　The　compressive　strength　and　slump　of　concrete　mixture　with　different　amount　of　crushed　oyster　shell　were　tested　and　thus　the　appropriate　dosage　was　determined.　Additionally,　the　compatibility　with　super　plasticizer　and　the　stability　in　Na2SO4　solution　were　also　discussed　to　prove　the　feasibility　of　oyster　shell　as　fine　aggregate　of　concrete.　The　microstructure　of　concrete　was　observed　with　XRD　and　SEM　techniques.　This　research　provides　the　basis　for　the　application　of　waste　biomass　calcite.