This study describes the use of the nominative object in infinitive clauses in Old Russian and Old Novgorod dialect. There are two competing constructions in this position: nominative object with infinitive and standard (accusative) object. The main goal of the paper is to analyze the choice between nominative and accusative case in these constructions. Nominative objects in infinitival clauses are considered in terms of differential object marking (DOM). The author compares nominative objects with unmarked objects in the Uralic languages. The most significant for the selection of case in this construction are word order and information structure.