KUSEINOVÁ, Darina, Bc.: Survey of the unethical behavior of the targeted company in relation to the customer [Graduation thesis] – Technical Univerzity in Zvolen, Department of Marketing, Trade and World Forestry. Thesis supervisor: Ing.Miriam Olšiaková, PhD. Degree of academic qualification: Engineer, abbr. ,,Ing.”. Zvolen: TU, 2018. 72 s.The diploma thesis deals with the research of unethical behavior of the selected company in relation with its customers. In the introduction of the diploma thesis there are explained basic terms such as business ethics, its principles, where and in what ethics in entrepreneurship is manifested and how to effectively implement it in practice. The second chapter focuses on the importance of marketing ethics and its presence in each marketing mix tool. The third chapter is aimed at research of business activities of a chosen company, namely Alza inc, which was realized by electronic questionnaires. The research shew misconduct in its relation with customers. The aim of the thesis was to find out if consumers have experiences with unfair behavior of the company. The summary of the thesis obtains how the different situations can be solved and where the consumer can turn if he notices with unfair practices by the seller.