Sussex Police are on the scene of a collision between three vehicles on the A283 Steyning Road near to the cement works.
Police were called to the scene at 4.55pm after one van and two cars collided, a police spokesperson said.
The road is currently closed in both directions, police said.
The vehicles are suspected to be badly damaged and are waiting to be recovered, police said.
Police do not believe anyone to be badly injured at this stage.
An ambulance and the fire service are also at the scene.
Traffic reports are indicating long delays from the Old Shoreham cement works up to the Lancing Manor roundabout.
Delays have also been reported north of Steyning.