The interior ministry suspended the party from official activities in February after Ben Ali fled abroad on 14 January during a popular uprising to overthrow his government.
The court "has decided to dissolve the Rally for Constitutional Democracy and to liquidate its assets and funds", the ruling said.
Pro-democracy activists have demanded that the party be dismantled since the fall of Ben Ali.
The party, which claimed a membership of two million people out of a population of 12 million, was accused of violating the constitution to set up a one-party "totalitarian regime" under Ben Ali.
Since its creation in 1988, the party had never been audited and had never filed annual accounts, the ministry added.