The 25-year-old from Dundee is only the third professional boxer to die in the UK from apparently fight-related injuries in the past 21 years.
St Andrew's Sporting Club  confirmed Towell's death in a tweet on Saturday morning.
Other tributes have been paid to the fighter on social media including an emotional post on Facebook from Towell's partner, describing her heartbreak at the loss of her "annoying best friend".
On Twitter, retired boxer Audley Harrison wrote that it was "sad news", and that he was "sending love and light to his family".
WBO world middleweight champion Billy Joe Saunders said "people need to understand boxing is not a game"
Fellow Scottish boxing professiongal Charlie Flynn said it was "hard to believe" what had happened.
Another professional boxer Tony Bellew said what boxers risk "every time we step through them ropes" had been highlighted again.
A fundraising page on the website JustGiving has been set up by former two-weight world champion Ricky Hatton.
It quickly attracted more than Â£10,000 of donations on social media.  The page hopes to raise Â£20,000 for Towell's family and young son Rocco.
Many tributes have been paid to boxer Mike Towell who has died in hospital after being seriously injured in a bout on Thursday.