Cucurbituril (CB) has recently been employed in many fields, including water purification, solar cells, energy conversion, and biomedical engineering. However, the poor solubility of CB poses a serious obstacle to the further development of CB applications. To enhance the solubility of members of the CB family (CB[5-8]) by preventing self aggregation in aqueous solutions, the synthesis of highly stable, rapid, and water-dispersible particles is presented in this paper based on a simple process that employs a nanocomposite composed of CB and amine-modified diatomaceous earth (DA). CB can be coated onto the surface of the DA and stabilized to produce a novel material that is useful for various applications. The nanocomposite (CB-DA) exhibited a strong host guest interaction, exhibiting a more than 100-fold increase in efficiency and greater stability in dye and pathogen encapsulation as a result of the host guest interaction, electrostatic interaction, and covalent bonding. We applied CB-DA to a commercialized filter system and were able to purify the water within 2 min. We believe that CB-DA will open a new avenue for the efficient utilization of supermolecular materials in aqueous molecular encapsulation applications.