The state Senate approved it Wednesday and Corbett's office says he's likely to sign it. The vote was 37-12.
The measure was spurred by the U.S. Supreme Court's decision that mandatory life-without-parole sentences for juveniles constitute cruel and unusual punishment.
The bill would create a new set of sentencing options, with penalties that depend on the age of the defendant and whether they're convicted of first- or second-degree murder.
Defendants 14 or younger would serve at least 20 years for second-degree convictions and 25 years for first-degree convictions. Offenders who are 15- to 17-years old would face at least 25 or 35 years.