The Assembly voted 67-1 in favor of the legislation.
Gov. Arnold Schwarzenegger still has to sign it.
The bill would not apply to commercial or licensed alcohol vendors.
Supporters of the bill say that it would deter adults from promoting underage drinking and reduce alcohol-related deaths.
Opponents argue that people age 18 to 20 are adults under most areas of the law and should be held accountable for their actions.
AP contributed to this report.