The paper deals with the studying of means of expression of the predicative centre of sentences with pronominal-infinitive complex on the semantic-syntactical and the formal-grammatical levels. Different approaches to the determination of syntactical matter of such constructions are defined, the fact of non-belonging of the infinitive to their predicative centre is revealed. The predicative centre of every type of sentences with pronominal-infinitive complex (two-member and mononuclear) is determined, the ways (structural-semantic and semantic) and means (modal and phasal lexemes) of their complication are described.