Acting Hetman () was a title during the 17th, and 18th centuries, in the Cossack Hetmanate. The acting hetman was the governing authority in the Hetmanate temporarily substituted for the hetman. The acting hetman was appointed by the hetman himself, to perform the duties of the hetman when absent during military campaigns, foreign travels, or his incapacitation. As well as a temporary replacement if the hetman's office became vacant, because of death, abdication, or deposition.