Seven fire crews from across Lincolnshire have been at the George H Kime and Co Ltd lorry depot since 1.37pm this afternoon. A water carrier from Holbeach is also at the scene.
The A52 was closed both ways between Wrangle and Old Leake at 2.30pm and there has been queueing traffic due to the fire and smoke blowing across the carriageway.
In the latest update from Lincolnshire Fire and Rescue, they said one warehouse measuring 100 x 60 metres was well alight.
"Fire has been surrounded. All persons are accounted for," the statement reads.