Teresa Giudice -- 'Real Housewives' Star Checks Into Prison

"Real Housewives of New Jersey" star Teresa Giudice is ringing in the New Year as an inmate ... after checking herself into prison early Monday morning.

Giudice will be serving her 15-month sentence at the Federal Correctional Institution in Danbury, Connecticut. According to our sources, Giudice showed up at 3:00 AM ... without husband Joe in tow. He was spotted later in the morning driving the couple's kids to school.

Giudice pled guilty in March to bankruptcy fraud and conspiracy to commit mail and wire fraud.

Once Teresa is sprung, Joe will serve a 41-month sentence for fraud. This way while one parent is behind bars, the other can do double duty.