Provided is a cooling tool that keeps a cooling object cold by utilizing the latent heat of a cold storage material and can visualize the physical condition of the cooling tool, i.e., can indicate whether the use condition of the cooling tool is appropriate. For example, when leakage of the cold storage material occurs, the cooling tool indicates the leakage of the cold storage material and shows whether the temperature is appropriate for keeping the cooling object cold. The cooling tool keeps the cooling object cold by utilizing the latent heat of a freezable material and includes: the freezable material that undergoes phase change at a specific temperature； a cold storage layer including a first container portion that contains the freezable material； and a condition indicator that shows the physical condition of the freezable material.
