Senator Piero Aiello is reportedly part of a wider investigation which led to 65 arrests this morning, ANSA news agency reported.
The senator is accused of buying votes with the help of the mafia.
The anti-mafia sweep has involved businessmen, politicians and lawyers, police spokesman Mario Viola told AFP.
A Calabrian councillor and doctor by profession, 57-year-old Aiello was elected to the senate earlier this year.
The region is home to the 'Ndrangheta mafia clan, one of the richest and most powerful organized crime groups in the world.