Business ethics represents an important aspect that influences each country’s socio-economic system, and is important to society, environment, and economy. The present article aims to define significant attributes of business ethics in the sector of small and medium-sized enterprises (SMEs) and compares their attitudes within the three most significant business sectors in the Visegrad Group countries (V4 countries: Czech Republic, Slovak Republic, Poland, and Hungary). An empirical study, focusing on the attitudes of small and medium-sized firms, was conducted in June 2022 in Visegrad Group countries through the reputable hired company MNFORCE, using the Computer Assisted Web Interviewing research method. The total number of respondents in the Visegrad Group countries was 1,398. Statistical hypotheses were tested using descriptive statistics, chi-square, and Z-score at a significance level of α = 5%. The most important conclusion of this research is that there are no significant differences in the approach of SMEs to business ethics based on the sector in which the companies operate. Some notable differences in attitudes among SMEs in Slovakia and the Czech Republic were identified, but these were marginal. Therefore, differences in the transformation process within selected economic sectors do not impact the formation of attitudes of small and medium-sized companies in business ethics. It is evident that business ethics is significantly determined primarily by the personal characteristics of the owner/manager of the company, and the specificities of individual sectors do not influence this field.