Valentin Demyanenko (Ukrainian: Валентин Дем'яненко), born 23 October 1983 in Cherkasy, is a Ukrainian and Azerbaijani flatwater canoer and former C-1 200m world champion.Demyanenko was a late developer and only came to prominence in 2004 with a shock victory in the C-1 500m final at the European under-23 championships in Poznań, Poland.