Anorexia nervosa (AN) is a psychiatric disease with a high prevalence and comorbidities, characterized by a low response rate to treatment. It is considered as a multifactorial disease. In recent years, the focus has been placed on the presence of intestinal dysbiosis and its possible involvement as a causal factor as well as an alternative treatment. The objective of this work has been to review the current state of knowledge of alterations in the intestinal microbiota identified in patients with AN and the possibility of using probiotics as a therapeutic alternative. Significant changes in the diversity of species associated with weight loss have been described that could favor the perpetuation of the disorder, and that would explain many of the nutritional, gastrointestinal, psychological, and cognitive alterations present in these patients. The use of probiotics, still little studied in patients with AN, sheds some light on this matter to improve the treatment response, always hand in hand with conventional treatments.