The research was focused on the effect of training and development on organizational performance byrnusing employee commitment as mediating variable. With the rising of new technology, nationalrnstrategy, national policy, and short term and long term organizational plan the knowledge and skill ofrnconcerned employees in service organizations should be competent and inculcate excellentrnperformance via contentious training and development on selective types of training like technical,rninterpersonal, problem solving, ethical skill and organizational learning. This study was needed tornanswer the gap on which types of training and development should organizations has focused onrngenerating commitment that provides good performance in Addis Ababa city administration revenuernauthority and trade bureau. The research was aimed to know the mediating effects of employeerncommitment between training and development, and organizational performance. The quantitativernapproach and descriptive research design in which the data was collected using questionnaires with arnconvenience nonprobability sampling technique was applied. SPSS and process macro that developedrnby DR. Andrew Hayes was employed analysis part. Indeed, all independent variables have positivelyrncorrelated with mediators and dependent variables. The finding from regression analysis indicatesrnthat R2 value is 0.382 which suggests that almost 38.2% change in the value of outcome Variable isrnexplained by Independent Variable. The unstandardized indirect mediation analysis report, trainingrnand development on organizational performance via mediating role of affective commitment wasrn0.0435 and was statistically significant(given that zero does not fall between the confident intervalrn0.0124, 0.0786).and the mediating effect normative commitment was 0.0326 and statisticallyrnsignificant or zero does not fall between the confidence interval 0.003, 0.633 and also a direct effectrnhas 0.0955 coefficient and statistically significant at a p-value of 0.00. The total effect was the sum ofrnthe two parallel indirect effects 0.0435 + 0.0326 = 0.0761 which is statistically significant becausernzero was not fallen between 0.026, 0.1115 and is interpreted as both affective and normativerncommitments can play mediating effect between training and development and organizationalrnperformance. Finally, the statistical significance of direct and indirect effects results in partialrnmediation. The research can contribute to governmental organizations by indicating the mediatingrnresults of employee commitment while providing interpersonal, technical, problem-solving, ethicalrnskill training, and organizational learning.