The man’s ordeal began on Wednesday at 8pm when he was bundled into a car on his way home from the university library, Sydsvenskan reports.
He was missing for 40 hours before being dumped by a motorway in the northern Polish town and police picked him up and took him to a hospital, where he remained on Sunday morning.
“He does not have any life-threatening injuries, but will be kept in under observation,” said Kent Öberg at the Swedish foreign ministry told Sydsvenskan.
Police suspect that there could be a racist motive behind the crime but remained uncertain on Sunday as to why the Swede was targeted.
Kidnapping is not a common occurrence in Poland, the newspaper reports, and Gdansk is not known to be a dangerous city.