Omalizumab is a recombinant humanized monoclonal antibody that reduces levels of circulating immunoglobulin E (IgE) and expression of IgE high-affinity receptors on mast cells and basophils, interrupting the subsequent allergic inflammatory cascade. Current indications for treatment with omalizumab in pediatric patients are clearly defined and are confined to moderate-to-severe uncontrolled allergic asthma and chronic spontaneous urticaria (CSU). Any other prescription can only be off label. Data available from clinical trials conducted in children suggest that omalizumab is clinically effective and generally well tolerated. Given its mechanism of action, recent reports have suggested its possible clinical use in other IgE-mediated disorders, such as allergic rhinitis, food allergy, and anaphylaxis. In recent years, several studies have also investigated the possible applications of omalizumab in a number of non IgE-mediated diseases. The aim of the present review is to assess all applications of omalizumab as therapy in the pediatric population. The approved indications--allergic asthma and CSU--are reviewed. Moreover, further potential applications of omalizumab are discussed in both IgE-mediated and non-IgE-mediated diseases.