The man, aged about 30, was not wearing a crash helmet when the accident happened just after midnight on A86 Paris outer ring road, one of the busiest motorways in France, a fireman said.
There was no immediate explanation as to why the man was on the motorway where electric scooters are banned.
The rider of the motorcycle, which crashed into the back of the scooter, suffered multiple injuries and has been hospitalised.
Electric scooters are increasingly popular in major cities and especially Paris but there have been several accidents, some fatal, since their introduction.
In June, a man died when his scooter was in collision with a lorry in central Paris, the first fatal scooter accident in the French capital.
In April, an elderly pedestrian died after being knocked down by a scooter in a Paris suburb.