Forest owner Evangelos Marinakis is desperate to steer the side away from relegation trouble.
The decision followed a goalless draw with Wolves at the City Ground, a match attended by Marinakis. Despite registering 35 shots against the league's bottom club, Forest failed to score and Dyche was booed by home supporters at full-time.
The result left Forest three points clear of the bottom three, but Marinakis subsequently held discussions with senior hierarchy members and players before concluding a change was required to improve their survival prospects.
Dyche, 54, had been in charge for just 114 days after his appointment on 21 October. Assisted by former Forest players Ian Woan and Steve Stone, he oversaw an encouraging start, beating Porto in his first game and securing a 3-0 win away to Premier League champions Liverpool a month later.
However, form deteriorated, with Forest winning only two of their last 10 league matches and taking just two points from fixtures against Crystal Palace, Leeds and Wolves. A January FA Cup defeat to Championship side Wrexham heightened internal concerns.
"Nottingham Forest can confirm that Sean Dyche has been relieved of his duties as head coach," the club stated.
"We would like to thank Sean and his staff for their efforts during their time at the club and we wish them the best of luck for the future.
"We will be making no further comment at this time."
Dyche followed Nuno Espirito Santo and Ange Postecoglou out of the door. Nuno, who had guided Forest to their first European qualification in 20 years before being dismissed in September, and Postecoglou, sacked after 40 days, were both removed earlier in the campaign.
Forest are now seeking a fourth manager, with former Wolves boss Vitor Pereira, previously employed by Marinakis at Olympiacos, among the leading candidates ahead of next Thursday's Europa League trip to Fenerbahce.