It is compulsory that complex social concepts should be defined in different ways and approached from the perspective of different science disciplines. Therefore, it is difficult to precisely define them without overlapping of meaning with other similar concepts. This paper has made an attempt towards theoretical classification of the national identity and differentiate that concept in comparison to the other related concepts (race, ethnic group, nation, national background, authoritativeness, patriarchy). Theoretical assessments are classified into two groups: ones that are dealing with nature of national identity and others that are stating one or more dimensions of national identity, crucial for its determination. On the contrary to the primordialistic concept of national identity, describing it as a fundamental, deeply rooted human feature, there are many numerous contemporary theoretical approaches (instrumentalist, constructivist, functionalistic), emphasizing changeable, fluid, instrumentalist function of the national identity. Fundamental determinants of national identity are: language, culture (music, traditional myths), state symbols (territory, citizenship), self-categorization, religion, set of personal characteristics and values.