UNLABELLED: Preterm neonates have immature body organs and even have stronger sensitivity towards environmental stress as compared with normal neonates. The NICU is a stress-causing environment because of noise produced from various sources like medical devices, monitor alarms, staff conversation, and the sound of cries from different neonates. The American Academy of Paediatrics recommends sound level should be less than 45 dB in NICU. A non-randomized, controlled, before-after, quality improvement, observational prospective cohort study was conducted on 100 preterm neonates. The samples were divided into two groups of 50 each: control and experimental. Physiological parameters were recorded, and the ABSS tool was used to assess behavioral responses. The control group received routine care, while the experimental group was provided with earmuffs. The study revealed significant improvements in physiological parameters and behavioral responses in preterm neonates using earmuffs. Experimental group neonates showed better thermal stability, reduced stress, improved respiratory and cardiovascular stability, and enhanced oxygenation (p <
0.002). Behavioral improvements included increased sleep duration and reduced restlessness, with statistically significant differences observed in all parameters compared to the control group. CONCLUSION: We conclude that the application of Earmuff is a fruitful method for preterm neonates to improve and stabilize the physiological parameters and behavioral response. WHAT IS KNOWN: • Excessive noise in NICUs causes stress and physiological instability in preterm neonates. • Noise reduction strategies, including ear protectors, help stabilize vital signs and improve neonatal outcomes. WHAT IS NEW: • This study confirms the effectiveness of earmuffs in improving physiological and behavioral responses in preterm neonates. • It demonstrates the feasibility of earmuff use in routine neonatal care within the study region.