The measure passed 62-27 Wednesday amid protests from anti-gun groups, black legislators and others.
The bill eliminates the duty to retreat in any place in which the person is lawfully allowed to be and makes concealed-carry licenses in Ohio and certain other states valid across state lines.
Republican Rep. Terry Johnson said the bill brings reasonable safety protections to Ohioans.
Democrats predicted it would foster violence. State Rep. Alicia Reece said opponents have jammed Republican Gov. John Kasich’s phone lines with calls to take their side.
At least 22 states have similar self-defense laws.