Greece is a parliamentary representative democratic republic, where the President of Greece is the head of state and the Prime Minister of Greece is the head of government within a multi-party system. Legislative power is vested in both the government and the Hellenic Parliament. Between the restoration of democracy in 1974 and the Greek government-debt crisis, the party system was dominated by the liberal-conservative New Democracy and the social-democratic PASOK. Since 2012, the anti-austerity, democratic socialist party Syriza has taken the place of PASOK as the largest left wing party, with their first election victory in January 2015.

The prime minister of the Hellenic Republic, colloquially referred to as the prime minister of Greece, is the head of government of the Hellenic Republic and the leader of the Greek Cabinet.