In recent times, natural hydrogels have been replaced with synthetic ones because of longer service life, larger water absorption capacity, and a larger variety of chemical resources. Hydrogels have been synthesized and explored for different applications. Recent developments in hydrogel technology have led to its use in wastewater treatment and biomedical fields. Finding a reliable and cost-effective wastewater treatment technique is a major concern worldwide for reducing environmental pollution. The simplest method to treat industrially contaminated water is by the adsorption technique. Hydrogels, polymers with a three-dimensional crosslinked arrangement, find their application in wastewater treatment because of their high adsorption capabilities and ability to be synthesized by green routes. The objective of this chapter is to collate different routes involved in the synthesis of hydrogels, emphasizing the knowledge gaps and providing a perspective for future development. A wide range of technical publications being examined to provide an overview of various hydrogel synthesis techniques for wastewater treatment applications. Technologies for hydrogel production with design implications and conditions for process preparation are discussed for free radical polymerization, ionic, chemical, and physical crosslinking, hydrothermal synthesis, electrospinning, and in situ gelation techniques. An advanced category of novel hydrogel materials and their synthesis are also discussed.