Background: Danger signs in the neonatal period are nonspecific and can be a manifestation ofrnalmost any neonatal disease. Early identification of neonatal dander signs by mothers withrnprompt and appropriate referral service are backbone programs aiming at reduction in neonatalrnmortality. In Ethiopia, a country where a neonatal mortality rate high, raising the awareness ofrnmothers on danger signs of neonate and appropriate care seeking behavior is crucial to sustain thernachievement done.rnObjective: To find out knowledge and health care seeking behavior about neonatal danger signsrnamong mothers visited immunization unit in selected governmental health centers, Addis Ababa,rnEthiopia, 2014.rnMethods: An institutional based cross-sectional study was conducted from November 2013-Junern2014 on a sample of 373 mothers from randomly selected 16 governmental health centers ofrnAddis Ababa, Ethiopia. The study participants were selected using convenient samplingrntechnique. A structured pre-tested questionnaire was used to collect quantitative data. Qualitativerndata was collected through in-depth interview with mothers. Data entering, coding and clearingrnwere performed using Epinfo version 3.5.4 and analyzed by using SPSS version 16.rnResult: Out of the total respondents about 280(77.1 %) mothers knew at least one neonatalrndanger sign. The most common mentioned neonatal danger signs were Diarrhea 58.9%,rnPersistent vomiting, 43.9%, and Fever, 32.9%. About 121 (39.5%) of mothers had seen a sickrnneonate with common manifestation of fever and health care was sought for 65.3% of sickrnneonates. Overall, most of the respondents 59.8% were a moderately knowledgeable of neonatalrndanger signs while 24.2% were highly knowledgeable, and 16% were poorly knowledgeable.rnKnowledge of at least one neonatal danger sign was significantly associated with health carernseeking behavior (AOR: 1.43, 95% CI: 1.04, 3.062, P=0.038), and motherâ€™s decision making onrnhealth care seeking (AOR: 2.031, 95% CI (1.001, 16.927, P=0.01).rnConclusion and Recommendation: This study indicated that the knowledge level of mostrnmothers about neonatal danger signs was moderate. Therefore, the identified deficiencies inrnawareness and health care seeking practice should be addressed through maternal and child healthrnservices by designing an appropriate strategies including provision of targeted information,rneducation and communication.