: Tusculana) is a Latin suburbicarian see of the Diocese of Rome and a diocese of the Catholic Church in Italy, based at Frascati, near Rome.

The bishopric moved from Tusculum to Frascati, a nearby town which is first mentioned in the pontificate of Pope Leo IV.

Pope John XXIII removed the Cardinal Bishops from any actual responsibility in their suburbicarian dioceses and made the title purely honorific.

Like other dioceses close to Rome, Frascati became a bishopric of choice for Cardinals of powerful papal families during the 17th century; a period known for its unabashed nepotism.

Frascati Bishops of that era were significantly intertwined: