Born in Thessaloniki, Kitsiou started out playing for local teams and he joined Pavlos Melas at the age of 14.
However he made it to the deciding play-offs and was introduced in the right side of the defense, (filling the void of injured Dimitris Konstantinidis) in the crucial last encounter against PAS Giannina.
[7] On 26 June 2017, the details of Kitsiou borrowing to Belgian club Sint-Truiden are of interest as they prove that the deal is identical to what was done for Charis Charisis.
[8] On 31 January 2019, Ankaragücü officially announced the signing of the Greek defender on a five-month loan deal.
[9] On 24 July 2019, Kitsiou made his move to Ankaragucu permanent after spending the second half of the season on loan in Turkey from PAOK.
[11] On 12 August 2021, Stelios Kitsiou has officially announced by Turkish club Gaziantep, signing a two years(with additional one) contract, for an undisclosed fee.
[12] On 28 August 2015, Kitsiou was among the calls of the Greek national football team's coach Kostas Tsanas for qualifying matches of Euro 2016 against Finland and Romania.