The research subject of the article are Russian phraseological units with the seme «indefinitely big quantity». Indefiniteness, including quantitative one, imposes difficulty on objective evaluation, and being combined with figurative reality reflection, which is characteristic of phraseological units, constructs lingua-creative way of verbalization of category of quantity in language. The aim of the research is to study axiological semantics of phraseological units with quantitative meaning of indefinitely big quantity taking into account the intensity of the seme «indefinitely big quantity». Quantification is a broader term than quantity, and incorporates not only quantity side of things, but also ideas of intensification and evaluation of quantity. The gradation of this seme in phraseological units is studied by their correlation with adverbs-explicators, which indicate the intensity of the quantitative parameter. Evaluative component in phraseological units with the meaning of indefinite quantity is created due to their structural characteristics as well as due to their semantics. Evaluation can also be ambivalent in character and can be interpreted only in the context of a concrete phrase. The degree of expressiveness of phraseological units with quantitative meaning need to be taken into account at creation of the texts of different types, in translation practice and other types of work with lexis. The research material was taken from National Corpora of Russian language.