To overcome the obstacles encountered in conventional aquaculture health management, nano-based medicines provide encouraging advances in the treatment of fish diseases by improving the delivery, effectiveness, and precision of medications. In fish aquaculture, conventional antibiotics and chemicals pose environmental concerns and economic losses when used to treat diseases caused by pathogens, including parasites, bacteria, and viruses. Nanotechnology solves some of these problems by enclosing medicines in nanoparticles, such as liposomes, polymeric nanoparticles, and nano-emulsions. This keeps medicines from breaking down, makes them more bioavailable, and delivers them specifically to infection sites. This targeted administration reduces the amount needed, reduces environmental contamination, and aids in the prevention of the development of antimicrobial resistance. Nano-based systems can also be set up to release therapeutic compounds in response to certain stimuli, such as changes in pH or temperature. This lets the treatment work in a controlled way and for a long time. Nano-formulations make essential nutrients and immunostimulants more bioavailable. This boosts immune function, lowers the risk of getting sick, and lowers the need for antibiotics. This is a huge step forward in managing aquatic animal health since nano-based treatments for fish diseases improve fish health and productivity while bolstering ecologically sound and secure aquaculture methods.