Sound production in seahorses has been largely overlooked, with limited research on acoustic diversity and associated behavioral contexts. The few existing studies identified mostly short-duration, broadband “clicks” emitted mainly during feeding, but also other sound types are produced during courtship, copulation, and stressful situations. Despite being an iconic and threatened species, research on how seahorses are affected by anthrophony remains particularly scarce. Underwater anthrophony can negatively affect fish physiology, behavior, communication, and fitness, with ultimate impacts on species survival. Considering that seahorses have poor swimming abilities, small home ranges, and high site fidelity, they are most likely threatened by environmental changes, such as acoustic disturbances. This chapter covers the present knowledge on (1) seahorse sound production and (2) the impact of marine traffic sound on their physiological and behavioral responses. An overview is provided from a critical perspective, considering the few existing studies, while highlighting potential future research and conservation strategies.