The construction industry plays a major role in the social, political and economic development of a nation. In spite of its contribution towards achieving social and economic development, the construction industry is plagued with a number of problems. One of these pressing problems is the unethical practice of professionals in the construction industry, which affects long-term business dealings, influence quality, time and cost. The main aim of this research is to analyze the effect of unethical practices and the stature of professionalism in the construction industry with emphasis on the City of Bahir Dar. The main tools for the collection of data included: questionnaires and panel discussions to evaluate and examine professional ethical practices on public building projects. The data compiled were analyzed statistically using relative importance index (RII) and statistical package for social studies (SPSS). The study made use of the quantitative and qualitative research methods. The results show that half of the respondents don‟t have a formal code of ethics/conduct in their organizations. The survey revealed that there were 52 un-ethical practices considered in this study and were listed under nine groups based on literature sources. From unethical practices, the contractors highly focus on profit maximization, leaking tendering information by the consultant, under-bidding, intentionally covering up poor workmanship and material quality and inadequate safety standards on site and lack of safety ethics was the first five most serious types of un-ethical behaviors observed. Also unethical behaviors seem to have negative impact on cost, quality and time. “Poor organization ethics, poor leadership and excessive love for money” are the most serious leading factors for construction professionals to become unethical. And lastly applying code of ethics application in organizations and leaders serving as role models are the top ways of improving professional ethical practice. The recommendation derived from the study is that, professionals pay more attention to all ethical standards in the industry. Finally, research and development should be organized in the public sector and the government is expected to take on this important issue to effectively address the concern.