The cornea is a transparent, dome-shaped tissue located at the front of the outer (fibrous) protective layer of the eye, and it has the ability to transmit light. In severe corneal damage where more than one layer of the cornea is affected, it is necessary to replace the damaged area and/or the entire cornea. In this case, although the transplantation of healthy corneal tissue from a donor to the diseased cornea, known as keratoplasty, is commonly preferred, issues such as donor limitations and allograft rejection may arise. To overcome these challenges, artificial corneal implants developed using biomaterials and tissue engineering techniques offer an alternative approach for corneal treatment. Due to their biocompatibility, high water retention capacity, tailorable shape, and flexible structure, hydrogel-based corneal tissue substitutes provide significant advantages. In cases of severe corneal damage, three-dimensional (3D) printing and bioprinting technologies are commonly used to develop a layered, organized, three-dimensional tissue substitute that mimics the light transmitting stroma layer. Hydrogels are the most frequently used bioinks, and cells can be easily loaded into hydrogels. Hydrogel-based constructs are commonly produced by 3D bioprinting or formed as thick slabs to develop tissue substitutes for corneal treatment.