Background: In 2016, an estimated 10.4 million people developed TB and of these more than 1.6rnmillion died from the disease, 374,000 (22%) of whom were HIV-positive. In most of the highrnburden of tuberculosis but resource poor countries, microscopy method issued in which acidfastrnbacilli are detected in smear using a light microscope. However, smear microscopy is not sornreliable. As of other most advanced tests, molecular techniques still not implemented inrndeveloping countries including Ethiopia. To improve MTB case detection rate, there is a need tornintroduce and implement rapid batch testing molecular methods in Ethiopia.rnObjective: The objective of this study was to assess the performance characteristics of Abbott realrntime for the diagnosis smear negative MTBrnMethods: Both prospective and retrospective cross-sectional survey was carried out to enroll 127rnstudy participantsâ€™ records along with left over sputum specimens in Addis Ababa, EPHI nationalrnTB/HIV laboratories from March to May 2018. Performance characteristics including sensitivity,rnspecificity and predictive values was calculated by using SPSS version 23 with 95% CI. For allrnstatistical significance tests, the cut-off point was 0.05 and p < 0.05 considered as statisticallyrnsignificant association with testing performance.rnResults: Diagnostic sensitivity of Abbott real time for the diagnosis of smear negative was 82.9%rnand specificity exhibited 89.1%. Drug susceptibility testing demonstrated diagnostic specificity ofrn87.5% and 100% for INH and RIF respectively. Abbott real time performance significantly andrnnegatively associated with month of treatment [Adjusted OR (95%CI) = 0.01 (0.00. 0.41)] for 1strnto 6th month, 0.005 (0.00, 0.20) for 7th to 12th months and 0.001 (0.00, 0.90) for the clients onrntreatment for more than a yearrnConclusions: The diagnostic sensitivity of the method for identification of MTB and drug resistancesensitivityrnand specificity similar with the previous similar studies. The method exhibited lowerrnspecificity for the diagnosis smear negative MTB cases. The finding also revealed the specificity ofrnAbbott real time the lowest as of other molecular methods for the diagnosis of smear negative MTBrncases who are on MTB treatment. Therefore, we strongly recommend not to use the method for allrnfollow-up MTB cases except zero month and further investigation should be continued to explainrnexhaustively the effect of explanatory variables on Abbott MTB performance.