Atopic dermatitis (AD) is a chronic inflammatory skin disease that commonly presents during early childhood. In the last decades the prevalence of AD has increased, especially in western societies. This frequently relapsing inflammatory condition has a strong impact on the quality of life of patients and families. The recent advances in the understanding of this disease have paved the way for the development of new strategies for the prevention and treatment of AD. Among the new therapeutic options, there is increasing interest in the potential benefit of probiotic supplementation. It has been widely demonstrated that the human microbiota plays a fundamental role not only in the maintenance of intestinal homeostasis through the interaction between microorganisms and the innate immune system, but also in the microbiota-mediated development of adaptive immunity. In addition, several studies have demonstrated that probiotics are able to influence the composition of gut microbiota and may exert immunomodulatory effects. According to these promising results, the possible application of probiotics in the therapeutic management of allergic diseases has been investigated in many studies. In particular, a considerable body of literature has been published analyzing the effects of probiotics on patients with AD. In order to shed light on frequently conflicting results, we reviewed the data regarding the application of probiotics in AD, with the aim to provide a state-of-the-art assessment of the most important studies exploring the role of probiotics both in the prevention and treatment of AD.