In the Yenisei inscriptions, as in Old-Turkic inscriptions in general, a great number of place names occur. However, Old-Turkic toponyms have not been studied satisfactorily. In this article emphasis has been laid on the word qatun mentioned in the inscriptions of Uyuk-Turan (E 3), Aldn-Bel I (E 12), Ald11-Bel II (E 72) and Novosyolovo (E 144). Having dealt with the meanings attributed to this word by previous researchers, it has been concluded that qatun in these inscriptions does not mean 'the wife of the khan' or 'woman', as hitherto supposed, but it refers to the river Katun. Furthermore, the name tarlay, which is often used together with qatun, denotes the river Tarlak.