"Let's raise some money to keep Gunnersaurus going. Please give generously!"
The dismissal comes on Transfer Deadline Day, where Arsenal could spend millions on players.
The football community took to social media to speak out in support of the mascot and life-long fan Quy.
"WHAT? This had better not be true. Is it @Arsenal ??!" tweeted Piers Morgan.
"You're going nowhere @Gunnersaurus. I refuse to let @Arsena sack you. Come on @m8arteta @Aubameyang7 - this is not what our club is about."
Gary Lineker said: "Shouldn't be necessary, but it might be a good move and an act of kindness for the @Arsenal players and manager to club together and sort out this absurdity."
Comedian Jack Whitehall joked: "This is so sad. Surely we just keep the costume and put [Mesut] Ozil in it?"
Former Arsenal player Paul Merson expressed his shock at the decision on Sky Sports News, saying: "Unbelievable. All them kids, the Junior Gunners, there will be 30 and 40-year-old fans who have grown up with that dinosaur.
"Its disappointing, I think it's poor by Arsenal, I really do."
