Dating from the time of the Roman Empire, the 2-inch marble bust depicts the head of a man with a short curly beard and almond-shaped eyes.
A statement Monday from the Israel Antiquities Authority says nothing similar has been found before in the country.
The archaeologists believe it could depict an athlete, possibly a boxer.
The figurine was believed to have been used as a suspended weight together with a balance scale, possibly by a merchant.
It was found in the ruins of a building destroyed by an earthquake in the fourth or fifth century.
Dr. Doron Ben-Ami and Yana Tchekhanovets, directors of the excavation at the site, described the high level of finish on the figurine as "extraordinary," and indicated that its features and positioning suggest Greek influence, indicating it should be dated to the time of the emperor Hadrian or shortly thereafter (Second to Third Centuries CE).
"This is one of the periods when the art of Roman sculpture reached its zenith," they stated.
(Left: Archaeological volunteer Nadine Ross of the United Kingdom displays a handful of 7th century Byzantine-period coins that she discovered at an excavation site outside the Old City of Jerusalem, Dec. 22, 2008.)