The 68-year-old former Penn State assistant coach arrived early in the morning at the State Correctional Institute at Camp Hill, just outside Harrisburg, a state prison system spokeswoman said.
He faces testing and evaluation that will take a week or more before he can be assigned a security risk level and sent to one of the state facilities as his "home" prison. At Camp Hill, experts will assess his mental state, physical health and education level, and determine whether he needs treatment.
Sandusky was sentenced this month to 30 to 60 years for sexual abuse of 10 boys over a 15-year period. He has repeatedly asserted his innocence and last week filed post-sentencing motions, seeking to have convictions thrown out or a new trial.
There are about 6,800 sex offenders serving time in Pennsylvania's prison system. The Corrections Department does not maintain special units for sex offenders, and there is no way to predict where he will be sent.