Barnet chairman Tony Kleanthous insisted he had no option but to terminate Ian Hendon's contract as the club battle to preserve their Football League status.
Hendon was given a two-year deal last summer and the Bees made a promising start to the season as they topped the table in September, but a poor run of form has seen them plummet down the table and they need a point at Grimsby on Saturday to avoid relegation.
Paul Fairclough will take over for the final two games of the season after Hendon was relieved of his duties on Wednesday.
Kleanthous told the club's official website: "Barnet simply cannot afford relegation and, after considering several options we are turning to Paul Fairclough, who achieves good results for the England C side, has experience and knows this club and the players."
He added: "Ian is a wholehearted hard working guy who was a great captain for the club and led us out of the Conference under Paul Fairclough.
"We gave him his chance in management midway through last season and he led us clear of the relegation area. As a result we gave him a two-year contract and the team started brightly enough. But things have fallen away and, although we brought in Peter Shreeves to help him, results have not improved and attendances have dipped.
"I have supported Ian throughout and given him every chance. I take full responsibility for appointing him and also perhaps for not taking action sooner. I am still sure that given the chance he will make a very good manager."
Copyright (c) PA Sport 2009, All Rights Reserved.