Sleep is a crucial factor for the psychological and physiological well-being of any human being. In Neonatal Intensive Care Units, preterm newborns’ sleep may be at risk due to medical and nursing care, environmental stimuli and manipulation. This review aims to identify the nurses’ interventions that promote sleep in preterm newborns in the Neonatal Intensive Care Units. An integrative review was conducted following Whittemore and Knafl’s methodology and the 2020 Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. The research was carried out on the electronic databases PubMed, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and ScienceDirect, with a timeframe from 2010 to 2021. A total of 359 articles were initially identified. After selection and analysis, five studies were included in the sample. Interventions by nursing staff that promote sleep in preterm newborns in the Neonatal Intensive Care Units fall within three categories: environmental management, relaxation techniques and therapeutic positioning. Nurses play a vital role in implementing interventions that promote preterm newborns’ sleep. They can positively affect preterm newborns’ sleep by controlling environmental stimuli and applying relaxation techniques and therapeutic positioning to their care practices.