This study aims to assess the Effect of Project Monitoring and Controlling Practice on ProjectrnSuccess in the case of Ethiopian Airlines Digital PMO. To achieve the objective of the studyrnExplanatory and Descriptive research design were used. As a result the researcher mainlyrndeployed quantitative type of research design. Data for the assessment are obtained through fivernpoint Likert scale based questionnaire from 43 selected respondents. Collected data was analyzedrnby using descriptive analysis, correlation and regression analysis using SPSS version 20.0. Thernresults of the collected data shows that there is good project monitoring and controlling practicernin the organization, however relatively there is weak project change control process in the PMO.rnResults also revealed that Pearson correlation between project documentation processes was arnmoderate with project success, and Pearson correlation between project progress report processrnand project change control process was a strong with project success. Regression results showsrnthat there was 60.7% of the change in project success was attributed to the combine effect of thernindependent variables in the model (project progress report, change control and documentation).rnThe overall project Monitoring and Controlling process groups have strong impact on projectrnsuccess, which means that high project monitoring and controlling had likely to generate higherrnlevel of project success. To be more successful in projects, the study recommend thatrnorganization must focus on project monitoring and controlling practice especially on the projectrnprogress follow up and project change control area as they have significant impact on the projectrnsuccess.