Flight EZY831 was due to depart at 8.20am but was delayed after police were called when the 37-year-old from Belfast became "increasingly abusive following a dispute over luggage".
Fellow passengers on the flight claim the argument began when the man tried to take two pieces of hand luggage on board, one of which was a "man purse". EasyJet allow their customers to board with only one piece of hand luggage, including handbags.
Niall Copeland tweeted that the man was "insistent on wearing his man purse" and said that during the argument the man tried to "insinuate" that easyJet's objection was “racially motivated".
Sussex police confirmed they attended the incident and took the man into custody after he was "tasered on the aircraft" while it waited to depart.
The man was arrested on suspicion of breach of the peace and obstructing and resisting a constable in the execution of duty. As of 4pm Thursday he was still in custody.
Sussex police said they had taken statements from witnesses among the crew and passengers.
An easyJet spokesman said that the incident took place due to the "passenger behaving disruptively".
The airline said: "EasyJet's cabin crew are highly trained to assess and evaluate all situations and to act quickly and appropriately to ensure that the safety of the flight and other passengers is not compromised at any time.
"Whilst such incidents are rare we take them very seriously, do not tolerate abusive or threatening behaviour onboard and always push for prosecution.
"The safety and wellbeing of passengers and crew is always easyJet's priority."