Background: The concept of ethical codes describes and explains morality of modern sportspersons. Authors of the article constructed a tool for assessing methods of moral behaviour in sport on the basis of the concept of ethical codes. The aim of this work is to present a tool for assessing a profile of moral behaviour of people involved in sport (both competitors, coaches and sports activists). Material/Methods: The Questionnaire of Sports Ethics consists of 52 statements which are classified into 5 scales that correspond to specific ethical codes. Respondents assess to what extent a form of behaviour described in the questionnaire is proper (praiseworthy, mark 3) or improper (needed to be condemned, mark −3). Results: The new tool is both reliable and accurate. Conclusions: A theory of 5 ethical codes organizes a multitude of worldview thoughts explaining the way of activities assessment in the sphere of sport depending on the culture.