Gastroesophageal reflux Disease (GERD) is  a very common problem among preterm infants, it is a challenging clinical entity that has often been associated with a number of negative clinical outcomes. The purpose of the study was to evaluate the effect of body positioning intervention program on relieving Gastroesophageal Reflux disease in preterm infants. The design of this study was a quasi - experimental research design. This study was carried out at Neonatal Intensive Care Units in Benha specialized hospital for children. A convenient sample of 60 nurses working at the study setting and a purposive sample of 60 neonates who suffering from Gastroesophageal reflux (GERD). Three instruments were utilized to collect data for this study; A structured interviewing questionnaire sheet, Observational assessment checklists and Pain assessment scales. The results of this study revealed that, nursing intervention in the form of body positioning guidelines improved medical outcomes of preterm infants with Gastroesophageal reflux disease on post program phase compared with preprogram phase. The study concluded that, preterm infants who exposed to the intervention program in the form of body positioning had better mean scores in relation to their medical outcomes post program compared with preprogram intervention. Therefore it is recommended that, intervention program in the form of body positioning should be applied to help in relieving Gastroesophageal reflux disease in preterm infants.