Background; Medical laboratory services are an essential component of health systems.rnStrengthening these services can combat the major infectious diseases. Laboratory accreditationrnsystem is found to be essential to have national and international acceptance of variousrnlaboratory test results. Poor quality laboratory services guide to massive causernof over-rntreatment, overuse of drugs which leads to the emergence of drug resistant and laboratory errorsrnguide the patients at risk of inappropriate care and potentially of adverse events .By recognizingrnthis gaps of the current state of laboratories and the requirements of ISO 15189 particularrnrequirements for quality and competence in Africa, Ethiopia, in 2009, WHO-AFRO establishedrnSLMTA in order to help laboratories with stepwise recognition of evolving fulfillment of thernISO 15189 standard instead of a grading of pass-fail.rnObjectives: To assess the outcome of Strengthening Laboratory Management TowardsrnAccreditation (SLMTA) on laboratory quality management system in Addis Ababa.rnMethods: The study used an Institutional based cross sectional study design that employed arnretrospective and prospective data collection approach on the participated institution of medicalrnlaboratory in SLMTA in Addis Ababa city government. The study was conducted in AddisrnAbaba city government and the data was collected from February â€“April 2014 and data wasrninterred in to EPI-data version 3.1 and was analyzed by SPSS version 20.rnResults; The assessment finding indicate that there was a significant improvement in averagernscores (141.4; range of 65-196, 95%CI =86.275-115.5, p = 0.000) at final with 3 laboratoriesrnbecome 3 star, 6 laboratories were at 2 star, 11 were at 1 star .76% of the respondents respondrnthat their facilities have no work plan and budget for laboratory specific purpose and lack ofrnresources accounts 24% is the reason for this which is followed by absence of System.rnLaboratory facilities which get adequate and timely manner mentorship were found 2.5 timesrnmore likely to get good success in the final status of improvement project (AOR= 2.501, 95%rnCI= 1.109-4.602) than which did not get it and those laboratory which didnâ€™t perform theirrncustomer satisfaction survey were 2.261 times more likely to get less final result than laboratoryrnwhich are conducting their customer satisfaction survey (AOR= 2.261, 95% CI= 1.851-6.007).rnConclusion: At the end of SLMTA 3 laboratories become 3 star, 6 laboratories were at 2 star,rn11 were at 1 star .The most important contributing factor for not scoring star in the final outcomernof SLMTA were not conducting their customer satisfaction survey, shortage of resource, poorrnstaff motivation, and lack of regular equipment service maintenance. Mentorship, onsite andrnoffsite coaching and training activities had shown that a great improvement on laboratory qualityrnmanagement system in most district laboratories.rnKeywords:-SLMTA, WHO-AFRO, Mentorship, Accreditation.