This paper examines the area of business ethics in subsidiaries of multinational companies operating in the Czech Republic. The empirical investigation involved 335 subsidiaries from sectors in which business activities in the Czech Republic predominate according to the official CZ NACE statistical european classification (Nomenclature generale des Activites economiques dans les Communautes Europeennes), with differentiation according to the size, legal form and ownership of the multinational company in the subsidiary operating in the Czech Republic. The results obtained indicate that a code of ethics has a significant prevalence in subsidiaries of multinational companies. It was demonstrated that the introduction of a code of ethics is related to the national culture of the head office, which is its main creator. By contrast, the effects of a code of ethics on financial performance are not statistically significant.