The collision happened on the A92 eastbound between Lochgelly and the Kirkcaldy West junctions at around 10.25am today, Police Scotland said.
The road has been closed while crash investigations take place.
Drivers have been advised that the diversion route is via the Lochgelly slip road, through Cardenden to Cluny, and rejoining the A92 at the Kirkcaldy West junction.
Meanwhile, a man has died following a one-car crash in north-east Scotland.
The 37-year-old, from Moray, died following the collision on the A941 near Rothes, Banffshire.
The crash, which happened at around 5pm yesterday, involved a single motor car, Police Scotland said.
The road was closed for approximately six hours for a collision investigation to take place.
Police are appealing for witnesses.