The Tigers' boss became the fourth Premier League manager to leave his post this season with the east Yorkshire club languishing second bottom of the league.
And Brown's replacement will have just nine games to save their season or face relegation and the end of their Premier League dream, just two years after promotion.
So who's next for the hot-seat at the KC Stadium? Sportsmail has a gander over the front-runners for the job.
Sacked: Hull have parted company with Phil Brown
Alan Curbishley - Bookies' favourite
After his protracted compensation battle with West Ham, Curbishley and his long-time assistant Mervyn Day are now available to manage once again.
Curbishley is considered favourite after he led the Hammers to safety two seasons ago, with seven wins from their last nine games.
Curbishley: Could he be the man to save Hull?
Steve Coppell - Experienced battler
Turned down the opportunity to move back to Crystal Palace a fortnight ago, not because he's bored of football but due to the short-term nature of the contract he was offered.
This may well prove the stumbling block as Tigers' Chairman Adam Pearson is unlikely to offer any replacement a contract past the end of the season.
Ready to return: But will Steve Coppell fancy the Hull job?
Gareth Southgate - One for the future?
Many feel he was somewhat harshly dealt with when ditched by Middlesbrough earlier this season.
Southgate was sacked in October, hours after a 2-0 victory over Derby County, and with the club lying fourth place in the Championship and a point off top-spot.
However, Boro spent most of the second half of last season in and around the drop zone, unable to pull away. This may rule him out of taking the reins for Hull's relegation scrap.
One for the future: Former Middlesbrough boss Southgate would surely welcome a return to football
Brian Horton - Safe pair of hands
Phil Brown's assistant has been instated as caretaker manager, alongside Steve Parkin. And Horton has the opportunity to wipe the slate with the Tigers after his last stint in charge ended in failure.
In the 1987-88 season, the Tigers, under Horton, went on a run of 17 games with just one victory and he was sacked.
And with the club in a state of malaise, chairman Adam Pearson may be looking for fresh blood to spirit the club away from the bottom three.
Horton: Could be the safe pair of hands that Hull need
Dean Windass - Fans' favourite
A hero at Boothferry Park, KC Stadium and, most famously, Wembley after his goal secured top-flight football for the first time in the Hull's history.
It would be a fairy-tale story if Windass helped guide the club to safety but he's a rank outsider who lacks management experience.
However, he's certainly a character who could galvanise the fans and players for the crucial run-in.
Hero: Windass is an extremely popular figure in Hull
Brown 'very disappointed' at being sacked by strugglers Hull CityPhil Brown sacked: Hull City end manager's reign as they fight to stay in the Premier LeagueHULL CITY FC