The article deals with the complex analysis of the concept Sviatvechir (Christmas Eve) of the microconcept-sphere Sviatki (Yule) projected for studying the peculiarities of its reflection in the synchronistical and diachronic aspects, as well as for clarifying of the specific character of its reflection in the hierarchical system of the linguistic world- mapping. Keeping within the limits of the lingvoculturological approach of the linguistic conceptology, in the research the notions such as conceptosphere, concept, conceptual microfield were considered. In the structure of the microconcept-sphere Sviatki 46 central concepts distributed to 10 conceptual microfields were distinguished. The appropriate field structure (nucleus, nearnucleus zone and periphery) of the microconceptosphere Sviatki was modeled and the hierarchical organization (superconcepts, presuperconcept, basic concepts, subconcepts) was presented. But the technique of the analysis of the lingvoculturological concepts suggested in this work consists of 3 stages: 1) formation of the nominative field of concept and definition of its nominative density; 2) description of the structural elements of the concept; 3) modeling of its field structure. During the analysis of every concept the means of its linguistic expression, including their paradigmatic and derivational peculiarities were characterized. The research of the central concepts of the microconceptosphere Sviatki permitted to discover the specific character of the national mentality of the Ukrainians within the limits of this fragment of the linguistic world- mapping.