The 27-year-old Portuguese was voted both players' player and Owls' fans player of the year in his first season with the club after being signed from Charlton last summer by previous manager Gary Megson.
Semedo said: "I still say to myself that I've made the right decision joining because if I didn't come here I would never know how big this club is or what it means to play for this club.
"To see Sheffield Wednesday in the Championship is the beginning of a good run for the club. It's the beginning of everything.
"I don't even think about leaving. Wednesday is my team, my club. I'm not interested in leaving."
Semedo, who has two more years left on his contract, has been an ever-present in League One this season.