The €1 and €2 coins were collected from scrapped cars and washing machines sent to China from Western countries.
The man, in his 40s, was detained in Austria earlier this year after police found 117kg (257lb) of the coins, worth €15,000 ($17,000; £13,000), in his car.
However an Austrian court has now ruled that his actions were not illegal.
The accused, referred to only as Mr H, had explained how he frequently travelled to China with cash to procure the coins, which he said were found in scrap metal items sent there to be destroyed.
He said that because the euro coins were not used as currency in China, he could purchase large quantities by weight at a fraction of their value and return to convert them for notes at Austrian banks using coin-counting machines.
His lawyer, Christoph Eberle, had maintained that the coins were not counterfeit, and that importing and converting the genuine old and damaged coins did not breach any Austrian law.
“My client used a bank coin mechanism designed specifically to determine whether a coin is valid or not. So there could be no deception,” Mr Eberle told AFP news agency.
According to Austria’s Kurier newspaper, some of the damaged coins were at some point subjected to a cleaning process to remove dirt and discolouration.
However, Mr Eberle had earlier said that his client was not aware of any process having taken place.
On Tuesday, his client was cleared of any wrongdoing.
The judge at the court in the Austrian city of Feldkirch ruled that, after reviewing “a balanced evaluation of evidence”, there was “no grounds” for prosecution.