The thesis deals with the market orientation of high-tech companies based in the city of Brno. It measures the effects of market orientation on business performance, analyzes the relations between market orientation and business performance for chosen companies and evaluates logical structure of the questionnaire used for marketing research. Based on the results of the research the thesis contains solution proposals addressed to the given companies, points out their weaknesses and follows with the proposals for the structure of the questionnaire and its future application for researching market orientation of the companies.