Sports Tonight will broadcast four hours of topical discussion seven days a week on Facebook, YouTube, mobile smartphones, tablets and eventually connected-TV sets.
According to The Guardian, the venture has £5m in financing and is backed by former Conservative party treasurer Lord Ashcroft, who has a minority stake.
MacKenzie described Sports Tonight as "Sky Sports News meets TalkSport", and said that he had been "wanting to do this for the last four or five years but the distribution wasn't there".
Former TalkSport presenter Mike Parry is among the first signings for the channel, ahead of its planned soft launch this summer before the start of the new Premier League season.
Parry and other presenters will be joined by two to four pundits debating any sports where there has been controversy. MacKenzie is also hunting for staff for the channel.
He added: "You will be ambitious and almost certainly yet to be discovered. Sport will be your drug and you have plenty to say but until now nobody was listening. Sports Tonight will change all that."
MacKenzie helped establish commercial station TalkSport after securing financial backing from Rupert Murdoch to acquire Talk Radio. The business was sold to UTV Media in 2005. He was also behind the Live TV channel in the late 1990s.
Yesterday, the former newspaper editor revealed that has joined the list of high profile public figures identified as alleged victims of phone hacking at the News of the World.
Speaking to The Guardian, MacKenzie said that he had been told by law firm Mischon de Reya, which is representing many of the phone hacking victims, that he was among those thought to have been targeted.
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