Background:Laboratory services are the back bone of current healthcare services, which isrnarticulated in different phases that span pre analytical phase, analytical phase,and post analyticalrnphases. Error can be any defect through the entire process of Laboratory services, from orderingrnrequest to reporting result. It may have harmful effects on patient managing, by contributing tornwrong treatment, an increase in lengths of hospital stay, and unhappiness with healthcarernservices. Therefore, this study aimed to Assessment of extra analytical errors and associatedrnfactors in Medical Laboratories of Public Hospitals in Addis Ababa, Ethiopia rnObjective: To Assess extra analytical errors and associated factors in Medical Laboratories ofrnPublic Hospitals in Addis Ababa, Ethiopia rnMethods: A hospital based cross-sectional study was conducted inMedical Laboratories ofrnPublic Hospitals in Addis Ababafrom January-April 2020 to assess extra analytical errors andrnassociated factors in medical laboratories.Data were collected from2401 laboratory requestformsrn(LRF) ordered within the study period and 169 lab professionals working in publicrnhospitals.Data were entered and analyzed using SPSS version 23.Data analyzed using simplerndescriptive statistics, percentages, frequency and summarized using tables and text.Thernassociation between dependent variable and independent factors were assessed using Chi-squarerntests. P-value < 0.05 will be considered statistically significant. rnResult:In this study, 2401 laboratory request forms were assessedand 169 lab professionals wererninterviewed. Out of the total errors 60.3% and 39.7% were recorded pre-analytic and postanalyticalrnerrorsrnrespectively.rnThernphysicianphonernnumberrnandrnpatientrnclinicalrndatarnwerernmissedrnrninrn97% andrn88.3%rnrnrespectively.Majority of the study participants were within the age group ofrn20-30 years (59.8%), Bachelor degree holders (62.7%) and have work experience of 6-10 yearsrn(39.1%).extra analytical errors in laboratory services were significantly associated withrnavailability of written procedures for laboratory activities(adjusted odds ratio (AOR) =2.79, 95% rnCI =1.34, 5.86), Experience (3-5years)rn(AOR) =6.69, 95% CI =1.85, 24.19) andEducationrn(Degree)(AOR) =6.30, 95% CI= 2.17, 18.26). rnConclusion and recommendation:This study reported re high frequency of errors in the extrarnanalytical phase. The information mostly absent in laboratory request forms assessed were rnphysician phone number followed by clinical data of patients and excessive TAT. Extrarnanalytical errors of laboratory can lead to misdiagnosis and mishandling of patients. So arncontinuous practice of measuringerrors andprovide capacity building, strengthening rncommunication between laboratory staff and physicians, apply rejection practice in incompleternLRF and specimen were required to help in reducing extra analytical error of laboratory.