Background: In Ethiopia neonatal mortality rate was 30 deaths per 1,000 live birthsin 2019. The survival of the child is determined at neonatal period. Neonatal danger sign refers to the occurrence of sign which show newborn mortality and morbidity. To reduce mortality and morbidity initial therapeutic intervention is necessary. Thus, family should be recognized neonatal danger sign and bring the newborn infant to health facility. Objective: the aim of the study was to assess knowledge about neonatal danger signs and associated factors among mothersin Sodo town, Wolaita Zone, southern Ethiopia. Method. Community based cross-sectional study design was employed from October 1st to 30th, 2019. Systematic sampling technique was used to select 410 mothers. A pre-tested, structured and interviewed-administered questionnaire was used to collect data. Data were entered using Epi-data version 3.1and analyzed using SPSS version 21. Bivariate and multivariable analysis was carried out using binary logistic regression to test and check the association between dependent and independent variables. Result. From 410 participants, 275(67.1%) (95% CI: 66.2%, 69.1%) of mothers had good knowledge regarding neonatal dangersigns. 226(54.9%) ofmothersidentified diarrhea as neonatal danger signs. Husband’s educational status secondary school (AOR: 3.84, 95% CI: 1.66, 8.89) and college and above (AOR: 2.41, 95% CI: 1.16, 5.03), place of residence (AOR: 2.04, 95% CI: 1.16, 3.57), Antenatal care service utilization (AOR: 2.79, 95 % CI: 1.49, 5.19), Postnatal care service utilization (AOR: 1.87, 95% CI: 1.18, 2.94) and mothers heard about neonatal danger signs (AOR: 2.14, 95% CI: 1.29, 3.54) were factors significantly associated with mothers knowledge about neonatal danger signs. Conclusion and recommendation: Although not satisfactory in views of expectation, relatively high level of mothers’ knowledge about neonatal danger sign neonatal danger signs had been observed in study area as compared with previous reports. The government, town health office, health workers should contribute to create awareness about neonatal danger signs in the community.