Oleksandr studied at Faculty of Chemical Technology of Igor Sikorsky Kyiv Polytechnic Institute extramurally, and received a bachelor's degree in Chemical technology. In 2016, he started the 1st year of the master's degree at the Faculty of Biotechnology and Biotechnics. From 2005, he worked at the learning and teaching laboratory of FBT.
In March 2014 he was called up for the Armed Forces of Ukraine. He took part in combat activities with 72nd Mechanized Brigade near the village of Zelenopillia in Luhansk oblast. After a serious illness, he was under treatment for a long time.
He left military service and returned to work at the university.
On April 1, 2017, Oleksandr suddenly died of an acute heart attack.
Oleksandr Kondratiuk’s name was immortalised on Bucha’s Memorial Walk of ATO Heroes.