A motorcyclist has died after her bike and a car collided in Coldstream in Melbourne's north-east on Sunday afternoon.

Ambulances were called to the accident scene on Maroondah Highway near St Huberts Road about 1.30pm.

Police believe a motorcyclist may have veered onto the wrong side of the road in a fatal accident. Credit:Nine News Melbourne

The female rider, who has yet to be identified, died at the scene.

At this stage, police believed the motorcyclist veered onto the wrong side of the road and collided head-on with an oncoming car.