The collision occurred between Gateways School and Wike Lane on the A61 Harrogate Road, near to the entrance of Harewood House, this morning (Saturday).
West Yorkshire Fire Service said a car had collided with a van, resulting in the van being on its roof.
Two people have been taken to hospital and three fire appliances are in attendance.
Reports say that there is slow traffic in the area as a result.
The Harrogate Bus Company tweeted to say services were being "diverted from Harewood straight to Moortown" and would not be serving stops in between.
Buses will be delayed as a result.
West Yorkshire Police confirmed they were called at 10.48am following a collision between a van and a Mercedes.
The road was closed and two people were taken to hospital, one of whom suffered serious injuries.