Hydrogels have intrigued significant interest in medicine owing to their porous structure and tissue adhesiveness, rendering them desirable candidates for drug delivery, tissue regeneration, and cancer management. Before injection, hydrogels should be liquid, but after injection, they should jellify quickly and form a soft, solid material. Injectable hydrogels enable a minimally invasive strategy compared to traditional surgeries with reduced cost and speedy recovery. Injectable hydrogels can be introduced into the target location using a catheter or syringe in a minimally invasive way. Injectable hydrogels hold great potential as biomaterials due to their superior biocompatibility, biodegradability, permeability, stimuli-responsive properties, tissue extracellular matrix (ECM) mimicry, and tissue regeneration ability. Supramolecular hydrogels can undergo reversible sol-gel transition concerning environmental stimuli, and noncovalent cross-linking has shown promising scaffolds for therapy. This book chapter highlights a detailed overview of minimally invasive injectable hydrogel, including materials for their fabrication and the process of gelation with various cross-linking mechanisms. Additionally, special emphasis has been given to the supramolecular hydrogel with minimal invasion and the therapeutic application of minimal invasive hydrogel in drug delivery systems and tissue regeneration.