The Heathrow-bound plane is surrounded by police and fire vehicles at Charles de Gaulle airport before getting the all-clear.
Passengers were evacuated from BA flight BA0303 as it waited to take off from Charles de Gaulle airport bound for Heathrow at around 8am UK time.
British traveller James Anderson, 20, posted pictures and video of the plane encircled by emergency vehicles on Twitter.
He wrote: "On British Airways flight BA0303, currently being held on tarmac at Paris due to security threat, surrounded by police and fire vehicles."
He later added: "Apparently an individual has made a direct threat to this aircraft."
British Airways said in a statement: "The safety and security of our customers and crew is always our top priority.
Police confirm a search of the aircraft found no threat and the alert was lifted.
Around three hours after its scheduled departure, at 11.10am, a BA spokeswoman confirmed the flight had taken off.
The UK's threat level is currently at its highest level - critical - after 30 people were injured in an explosion on a London Underground train at Parsons Green in southwest London.