
The attacker was also critically injured, the police chief, Laurent Nunez, told reporters.
France is on its highest state of security alert as it gears up to host millions of visitors, athletes and world leaders during the Paris Olympic Summer Games, due to kick off on July 26.
Paris police called on people to avoid the Champs Elysees area.
Television footage showed armed police condoning off the famous avenue.
The attack was the latest in a string of unrelated security incidents in the French capital this week.
A soldier was stabbed and wounded by a man armed with a knife at a railway station on Monday. Authorities are also investigating whether a man who rammed a car into the terrace of a cafe on Wednesday evening did so deliberately.