The collection of old printed and rare books is the pride of the university. The exposition is located in the sacristy of the temple and is a separate thematic section of the university museum. Today the collection contains editions of the largest Ukrainian printing houses of the XVII-XIX centuries, in particular books of the Lviv Brotherhood and Kyiv Lavra Printing House of the XVII century, Pochaiv Lavra of the XVIII century, Suprasl Printing House of the XVIII century, foreign editions. Rare books of the XIX-XX centuries are kept here. Thus, the exposition consists of several thematic blocks that reproduce the history of Ukrainian book printing. At the same time, the collection includes foreign publications, which are collected in a separate thematic section.
The uniqueness of the collection is not only in the value of the exhibited books but also in the fact that patrons donated all the volumes to the Ostroh Academy. Collector Ivan Kardash donated a significant number of books, so the collection is named after him.