A questionnaire study of eminent scientists' professional values was carried out within more extensive research of professional ethics. The structure of scientists' professional values is composed of five factors: collegial and professorial responsibility, the protection of respondents or patients, wider social and professional responsibility, scientific precision and originality and scientific objectivity. The core of the scientists' professional code consists of the values with the highest ratings. These are: cognitive standards which define the research role, explicit expectations of the scientists' social responsibility, and requirements for excellence of scientific institutions and personnel. At the same time, significant differences have been found among the observed scientific fields. The largest discriminative power has been shown in the importance of precise measurements and then also in the protection of respondents and patients. These results question the traditional unitary concept of science, but also the concept of intellectual and social atomisation of scientific disciplines and fields.