Antimicrobial resistance (AMR) represents an escalating global health challenge, with aquaculture emerging as a significant contributor due to its extensive and often unregulated use of antibiotics for disease control. This review investigates the emergence and transmission of AMR within aquaculture systems, where excessive antibiotic use selects for resistant bacterial strains capable of survival and replication. These bacteria disseminate resistance genes through horizontal gene transfer mechanisms, including transformation, transduction, and conjugation, facilitated by mobile genetic elements. The implications are far-reaching, including increased disease outbreaks in farmed fish, elevated production costs, trade barriers, and serious public health concerns via contaminated seafood and environmental pathways. Tackling AMR in aquaculture demands urgent interventions, including prudent antimicrobial use, improved aquaculture practices, development of alternative treatments, and coordinated One Health approaches that integrate human, animal, and environmental health strategies.