The two-seater plane landed at 3:15 p.m. in the center divider of the Foothill Transportation Corridor at Oso Parkway, the California Highway Patrol said. No one was injured.
The $150,000 plane appeared to be intact after touching down.
Two mechanics were seen removing the plane's wings so it could be transported from the toll road.
No road closures were reported.
An investigation into the incident is underway, authorities said.