Oleksiy Petrovych Tolochko is a Ukrainian historian and medievalist, doctor of historical studies, and corresponding member of the National Academy of Sciences of Ukraine. Tolochko is the director of the Centre of Kievan Rus' Studies in Kyiv, and is known for his work on textual criticism of the Primary Chronicle.

Textual criticism or textology of the Primary Chronicle or Tale of Bygone Years aims to reconstruct the original text by comparing extant witnesses. This has included the search for reliable textual witnesses ; the collation and publication of such witnesses; the study of identified textual variants ; discussion, development and application of methods according to which the most reliable readings are identified and favoured of others; and the ongoing publication of critical editions in pursuit of a paradosis.