Wednesday are currently third in the League One table with 13 games left to be played.
Wednesday chairman Milan Mandaric said: “This was a very difficult decision but one that has been taken with the best interests of Sheffield Wednesday at heart. We have 13 games to go of what is a critical season for our club.
“This decision has been taken because I believe we have a better chance of achieving our key aim of promotion by making the change.
“I fully understand this may not be the most popular decision amongst our supporters. But I ask them to trust me, as they have done so whole-heartedly during the time I have been at the club. While we won what was a huge game last Sunday, I have looked at results before that to reach the conclusion which I believe is the right one for now and the future of Sheffield Wednesday. I take no decision lightly regarding this club and this one is no different.
“One chapter is closed and another one begins. We must now look forward and I hope to appoint a new manager as soon as possible to help achieve success for this club.”
