This study intends to quantitatively assess how project personnel (managers, managing directors, team leaders, supervisors, and engineers) in the two Ethiopian developmental projects (Abay Garment and Amhara Metal industry and Machine Technology Development Enterprise) that were chosen for study perceived the effect of human competence on project success. Five dimensions for human competence elements intellectual competency, emotional competency, managerial competency, skill competency, and leadership competency as well as four factors related to project success cost, time, quality, and environmental impact were found following a thorough review of the relevant literature. In total, 72 relevant surveys from the two developmental initiatives were gathered. The theoretical framework was tested using the structural equation modeling approach. In this thesis finding, two human competence characteristics are critical for startup developmental projects to complete their projects successfully. These two competencies skill competency and leadership competency fill the knowledge gap in the literature on human competence and project success by being the most important predictors of project success in both types of developmental projects. However, managerial, intellectual and emotional competencies were found to have no significant relationship to project success. In terms of a new perspective, this thesis investigates the impact of five human competences on project success and gives an evaluation of the effects on human competence and project success in the two developmental projects from the point of view of both analytical and structural links. Based on the thesis results, recommendations were forwarded that enterprises, industries, and other interested organizations may find useful. Keywords: Human Competence, Project success, Structural Equation Modeling