The truck, carrying timber, was driving across an unguarded railway crossing when the train collided into it and derailed.
Pictures from the scene showed the train, still standing, lurched off the track and badly damaged.
But the truck, which took the most impact, could be seen in a mangled wreck on a field a few hundred yards away.
@POLSATNEWSPL ON TWITTERWRECK: One of the first pictures taken moments after the train collided into a truck
@RADIO_SZCZECIN ON TWITTERDESTROYED: The truck was pictured wrecked on a field metres away from the train
The crash took place in Daleszewo, northwestern Poland at around 1pm local time this afternoon.
All emergency services were in attendance as the railway line was shut for the rest of the day.
It was reported the driver of the truck had died, while the dozens who were injured were in "severe" conditions.
@POLSATNEWSPL ON TWITTERTERRIFIED: Passengers who escaped uninjured were left in shock on the tracks
Local reports also said it was possible the number of injured passengers would rise.