Cost and time overruns are prevalent problems in the Ethiopian construction industry significantly affecting the overall economy of the nation. Researche studies have indicated that one of the main causes for cost and time overrun is related to the poor performance of stakeholders. This research was conducted to study stakeholders role in minimizing cost and time overrun. In order to achieve the research objective, both qualitative and quantitative research methods and multiple sources of data collection were used including, questionnaires, semi-structured interviews along with collecting and reviewing literature and case studies. A total of 113 questionnaires were distributed for main stakeholders including contractors, consultants, regulatory bodies and clients. 16 experience respondents were also selected for interviews and seven active public projects were selected for case study. A pilot test, Cronbach's alpha, and Spearsman correlation were used to check the consistency or reliability and validity of the research instruments respectively. The collected data were analyzed using Excel and SPSS. Relative Importance Index (RII) was used to rank the cause of cost and time overrun and stakeholders’ level of influence in minimizing cost and time overrun.The result of the research indicated that the main causes for cost and time overrun are related to the knowledge, decision, and experience of the involved parties. Stakeholders performance have an impact on project success. Depending on their influence clients were found to be the first responsible stakeholder in affecting the project success, while consultants and contractors are ranked as second and third respectively and regulatory bodies as last. The result of the findings show that the poor performance of one stakeholder has a great impact on other stakeholders’ performance and affects the overall performance of the project. Generally, in order to minimize cost and time overrun, all stakeholders should be responsible and clearing roles and responsibilities among stakeholders are essential.