Background: The prevalence of obstructive sleep apnea (OSA) in children, which can lead toexcessive daytime somnolance (EDS), failure to thrive, cardiovascular disorders and respiratory failureand death, continues to rise. Inflammation is associated with OSA. Purpose: To identify the role of neutralendopeptidase (NEP) to inflammation in obstructive sleep apnea (OSA), and its association to inflammatorymediator subtance P (SP), interleukin-4 (IL-4) and tumor necrosis factor-α (TNF-α). Methods: A crosssectionalstudy had been done to 36 adenotonsilar hypertrophy child patients with OSA during the periodof time from May 2013-2015. OSA was diagnosed based on polisomnografi and the level of NEP, SP, IL-4and TNF-α by imunohistochemistry. Results: We found 21 subjects had OSA (58.3%) and 15 subjects didnot have OSA (41.7%), from total sample 36. There were significant associations between SP tonsil, SPadenoid and IL-4 tonsil with OSA (p<0.05). Although the number of NEP level in OSA was smaller thannon OSA and IL-4 adenoid, TNF-α tonsil and TNF-α adenoid OSA were found greater than non OSA,but the difference between them were not significant (p>0.05). Conclusion: This study did not found asignificant correlation between NEP with OSA but there were significant correlations between SP andIL-4 with OSA.