The man died at the scene after he crash landed into a field near Lubenham, Leicestershire, just before 1pm.
He had collided with a light aircraft that managed to land safely at Market Harborough.
Leicestershire Police has launched a joint investigation with the Air Accidents Investigation Branch.
A police spokesman said: “From initial enquiries carried out at the scene, officers believe the glider had been in collision with a light aircraft prior to coming down in the fields.”
“The man on board the glider has been pronounced dead at the scene.”