The purpose of the study was to identify the Effects of the project managerâ€™s leadership quality on the project success of World Vision Ethiopia, Addis Ababa. the data was collected from 56 PMs of world vision Ethiopia who work on projects. The data collection was done through Questionnaires measuring the Project Manager's characteristics, emotional intelligence, technical, and soft abilities on project success. Data from the quantitative survey were analyzed using frequency, percentages, mean, standard deviation, Pearson Correlation, Multiple Linear Regression, and ANOVA using SPSS version 26 software. The results of the study revealed that there is a strong link between project manager leadership characteristics and project success; with the soft skill of the project manager having the largest impact on project success followed by emotional intelligence, personal characteristics, and technical skill. The finding from the Pearson moment correlation revealed a statistically significant positive correlation between personal traits, technical skill, soft skill, and emotional intelligence. The researcher, therefore, concludes that Among the leadership qualities examined, the soft skill of the leader was determined to contribute the most to project success. Soft leadership abilities contribute more than technical skills in this study. Therefore, The researcher recommends that to enhance the success of projects that the organization ought to be conscious of the value of personal characteristics, emotional intelligence, and soft and technical abilities when recruiting a Project Manager for enhanced success.