A stacked wafer structure includes a substrate; dams provided on the substrate and having protrusions on a surface thereof; and a wafer with recesses provided on the dam. The protrusions on the surface of the dams are wedged into the recesses of the wafer, preventing air chambers from forming between the recesses of the wafer and the dams, so that the wafer is not separated from the dams due to the presence of air chambers during subsequent packaging process. A method for stacking a wafer is also provided.