The 152 silver Arab and Persian coins were struck in different parts of the Middle East and represent the single-biggest collection of Arab coins dating from the period to be found in Denmark, Xinhua news agency reported the Bornholm Museum as saying.
An amateur archaeologist found the first coins in September with the museum conducting subsequent excavations.
Such early Arab coins are rarely found in Scandinavia, archaeologists said.
The treasure was hidden in a house in an early Viking-era settlement and reflect a tendency for people at the time to safeguard treasures by burying them under the floors of houses, they said.
The coins probably came to Denmark as a consequence of the Vikings' trade with Eastern Europe and reveal Bornholm Island's former importance in the Baltic trade system, researchers said.