Three of the environmental activists suspended themselves from the top of the building in downtown Ankara, but did not manage to unfurl a giant banner reading "Nuclear power is a sham. The minister has no clothes" as the police and ministry officials intervened.
Fellow demonstrators outside the building brandished placards reading "No to nuclear energy" and "Don't trust the nuclear tales."
Overriding strong opposition from environmentalists, the energy ministry last month invited bids for Turkey's first nuclear power plant, to be built at Akkuyu, on the country's southern Mediterranean coast.
An earlier plan for a reactor at Akkuyu was scrapped in July 2000 amid financial difficulties and protests from environmentalists in Turkey, Greece and Cyprus.
Opponents raised safety concerns on the grounds that the proposed site was only 25 kilometres (15 miles) from a seismic fault line.