A woman has been rushed to hospital with serious head and internal injuries after a major crash involving a truck, two buses and multiple cars in Sydney's north-west on Tuesday morning.

The crash occurred about 10.15am near the intersection of Church Street and Junction Street in Ryde.

The crash has left a woman fighting for life in hospital. Credit:Seven News / Twitter

A police spokesman said a truck and an Audi crashed, with the truck then crashing into a bus and several vehicles. The impact of the collision caused the bus to crash into a second bus.

The female driver of the Audi was trapped and had to be rescued from the vehicle.