The Insurance Institute for Highway Safety said the 2012 500 Sport two-door had earned good marks for front, side rollover and rear crash evaluations.
Results reflect performance in crashes that would occur with similar-sized vehicles. The only other mini car to earn similar scores was Ford Motor Co's Fiesta.
The top score for front crash resistance was earned during a retest in August after Fiat/Chrysler modified front seating to make it more secure, the IIHS said.
Chrysler is counting on the hatchback 500 and other fuel-efficient vehicles to revive its lineup, which is dominated by pickups and other light trucks.
The IIHS assesses a range of models each year. Underwritten by the insurance industry, the institute's ratings are closely followed by automakers, consumer groups and safety regulators.
