Patients with chronic diseases, including chronic respiratory diseases, usually have considerably impaired sleep quality that may increase the frequency of exacerbations and severity of symptoms, lead to difficulty in patient management, and reduce quality of life (QOL). During the last few decades, several studies have shown that, in addition to the classic signs of sneezing, nasal itching, rhinorrhea, and nasal obstruction, allergic rhinitis has an important impact on the QOL of adults and children. In 2001, the ARIA (Allergic Rhinitis and its Impact on Asthma) report based its new severity classification on the impact of rhinitis on QOL, with the inclusion of sleep disturbances. Thus, allergic rhinitis patients may also suffer from sleep disorders, emotional problems, as well as impairment in daily activities and social functioning. Given that sleep is fundamental for physical and mental health, the present document reviews the methods and questionnaires used to assess the quality of sleep, the importance of sleep in allergic rhinitis, impairment and improvement of sleep in allergic rhinitis by using medications (antihistamines, topical nasal corticosteroids, nasal decongestants, antileukotrienes) and, finally, the relationship between the sleep apnea syndrome with allergic rhinitis and its treatment.