ABSTRACT With aquaculture intensification, improving feed intake in order to increase fish growth as well as to reduce production costs and environmental impacts assume a high importance. In this sense, probiotics and prebiotics' capacity to positively modulate animals' appetite is of high interest and has been the focus of several studies in mammals, while in fish these studies are scarce, and available information is dispersed. Probiotics and prebiotics' role in appetite regulation mechanisms can be mediated by short‐chain fatty acids produced by gut microbiota, or by several other microbial‐derived metabolites, proteins, and lipopolysaccharides. The possible way these molecules may affect fish appetite is the focus of this review, which also highlights novel research directions for better elucidation of the impact of probiotics and prebiotics in the regulation of fish appetite, contributing to the definition of better feeding strategies, that optimize feed utilization efficiency and fish growth, leading to a more sustainable aquaculture production.