In Japan, scallop shells are considered to be industrial waste. Thus far, attempts for reusing these shells have been mainly limited to the commercial production of CaCO3. Nevertheless, there are no clear economic benefits associated with the use of scallop shells as a source of CaCO3. Hence, we are attempting to investigate a new value-added use for scallop shells as an advanced functional material. In this regard, we focused our attention on nuclear wastewater, which contains radioactive Sr and Cs. Sr, which tends to accumulate in bones, is believed to cause bone cancer. Hence, it is highly desirable to develop a method for removing Sr from contaminated water. In this study, we investigate whether scallop shells demonstrate the ability to remove Sr from a solution. From the results obtained, scallop shells can remove Sr solutes from a solution; furthermore, as compared to CaCO3, they demonstrate superior ability for removing Sr.