Materials with self-healing property are considered as the smart materials for various advanced technological applications. Previously only living substances such as tissues were thought to have self-healing properties that are required for their survival and adaptation to environmental changes. Recently, novel synthetic materials such as hydrogels have been prepared and developed which demonstrated self-healing performances. Exceptional self-healing has been observed in hydrogels introducing different kinds of nanoparticles. These hydrogels have exceptional functionality and mechanical properties. The techniques of the introduction, exploration, and measurement of the properties related to self-healing are challenging due to the wide variety of substances. In this chapter, efforts have been made to discuss the mechanism, types, and drawbacks of nanomaterial-modified self-healing hydrogels.