Brain drain is the exit of employees who hold any skill, competency, or personal attribute that may be considered highly needed and valuable organizational assets. This cross-border movement of skilled human resources staying a broad for extended periods of time is a growing phenomenon severely affecting the African continent. In order to investigate its causes and characteristics, this study has examined empirical evidence on two public institutions in Ethiopia. From the sample respondents, the researcher has found that although the causes of brain drain in Ethiopia are multifaceted, the major one are poor remuneration system and political inconvenience. Because other studies have also indicated that the causes of brain drain in developing countries are similar; the findings and the researcher''s recommendations in this study could be used by other government policy makers, private organizations and other institutions that have involved in mitigating the problems of brain drain.