The research presented in this paper is a part of the project “Condition, Factors and Development of European Identity in Serbia and Montenegro”, which started in 2002 with the financial support of the Ministry for Science and Protection of Environment of the Republic of Serbia. The research studied the relation between certain kinds of social identity ( European, i.e. national identity ) on the one hand, and the degree of rigidity of the subjects on the other. The sample consisted of 2685 inhabitants of Serbia and Montenegro, of both sexes, different levels of education and 18 to 43 years old. European, i.e. national identity was measured with the questionnaire EUROID2002, which consisted of 36 items related to different aspects of social identity. Factor analysis singled out five factors of social identity: pro-European orientation, advocating the preservation of national identity, confronting traditional values and technological civilization, globalization as a threatening factor for small and poor nations, and exclusive national attachment. Rigidity of the subjects was determined with the application of the RG-2 questionnaire which consists of 30 items related to the rigidity of thought in various life situations. Factor analysis singled out two factors of rigidity: rigidity toward oneself and others, as well as rigidity in one’s life habits. The relation between social identity and rigidity was determined with the technique of canonical analysis. Two significant canonical roots were singled out: the first canonical root includes two aspects of rigidity which were positively related to the factors implying a strongly pronounced national identity ( advocating the preservation of national identity and exclusive national attachment ). The second canonical root indicates a positive relation between rigidity in life habits and traditional standpoints and fear of globalization.