Background: Newborns are the future generations and ensuring their healthy growth and development and all the activities regarding them must be the prime concern of societies. The Ethiopian government has used a combined efforts and interventions in health promotion, nutrition, and non-health sectors at different levels to reduce neonatal mortality but still has high neonatal mortality. The objective of this study was to assess the magnitude of neonatal mortality and associated factors among Neonates admitted in neonatal intensive care unit of Arba Minch general hospital.

Method: A cross sectional study was conducted from January, 01, 2015 to December, 31, 2017 G.C in Arba Minch General Hospital. Simple random sampling technique using computer generated random numbers was used to recruit the predetermined 332 samples. Data were collected using structured checklist and entered, coded, edited and cleaned using Epi-info version 7 and exported to SPSS version 23 for Windows. Crude and Adjusted Odd ratio, 95% CI and P-value were used to assess the strength of association and statistical significance. Variables which have p value <0.05 were declared as significant.

Results: The magnitude of neonatal mortality was 20.2%. The 5th minute APGAR score less than five (AOR:4.4; 95%CI: 1.98,9.65), Induced labor (AOR:2.7; 95%CI: 1.03,7.37), Duration of labor > 18 hour (AOR:2.6; 95%CI: 1.12,6.11), Time of rupture of membrane >12 hour (AOR:3.9; 95%CI: 1.5,9.87) and Birth order > (AOR:19.5; 95%CI: 6.84,55.45) were the independent factors which cause neonatal mortality.

Conclusion: The magnitude of neonatal mortality was high and the fifth minute APGAR score less than 5, Induced labor, Duration of labor more than or equal to 18 hours, Time of rupture of membrane more than or equal to 12 hours before delivery and being fifth or above birth order are the independent factors which cause neonates to die.