Saidy Janko (born 22 October 1995) is a Swiss professional footballer who plays for Spanish club Real Valladolid.
Although Janko primarily recognised as a right-back, he is equally capable of playing on the right wing.
Janko began his career with FC Zürich before signing for Manchester United in 2013. After a loan spell with Bolton Wanderers, Janko moved to Scottish club Celtic in 2015. He had a loan to Barnsley before moving to Saint-Étienne permanently in July 2017. He has played international football for Switzerland up to under-21 level.
On 1 October 2020, Real Valladolid signed Janko on a four-year contract to end in 2024, for an undisclosed fee. He made his debut in La Liga 24 days later in a 2–0 home loss to Deportivo Alavés.