Background: Prematurity is one of the most important problems of recent years, and the number of premature infants is increasing every year. Babies who are born prematurely due to defects in the coordination of swallowing, sucking and breathing require mouth tube or nasogastric intubation feeding. Because bolus gavage feeding is more appropriate physiologically and improves the secretion of gastric hormones is more common in neonatal intensive care units. Objective: The primary objective of the study is a comparison of two alternate gavage ways with force gravity and injection with syringe in premature infants and find existence difference and compared with the results of the research have been performed yet. Methods: In this study, gastric residual volume indicators collecting method are used. The study used a questionnaire to collect data to measure indicators of the following tools. Results: Results showed that both alternate gravity and injection (push) ways, complications of gavage (vomiting, aspiration, abdominal distention and necrotizing enterocolitis) had not been seen. Conclusions:  Based on the results of both currently study of methods in preterm infants feeding have same effectiveness and safety.

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