Public broadcaster Polish Radio reported, however, that no-one had suffered life-threatening injuries.
German police said the coach was heading to Hamburg at 5.35am when it veered out of its lane, hit a barrier and toppled onto its side.
Polish citizens were among those injured, said Ewa Suwara, a spokeswoman for the Polish foreign ministry.
She added that efforts were being made to establish the exact number of Poles involved and what condition they were in.
(pk)
Source: PAP/Polish Radio