Chinese student Ye Mengyuan, 16, survived the July 6 crash, only to be run over by a fire truck while she was covered in firefighting foam, authorities said.
Prosecutors said on Friday that their investigation determined it was a "tragic accident," and that the firefighter driving the truck broke no laws.
In all, 304 of the 307 people aboard the Boeing 777 survived the crash, although dozens of people were injured.
Ye and a friend were seated at the back of the plane that approached landing too low and too slow, clipping its landing gear and tail on a rocky seawall just short of the runway.
It's not clear how Ye got from the plane to the spot where she died. Investigators believe she was down on the ground and not standing during the aftermath of the plane crash.
The cause of the crash is under investigation. The National Transportation Safety Board has said it did not find any mechanical problems with the plane during a preliminary review.
However, the plane's pilots and Asiana have raised the possibility that a key device that controls the Boeing 777's speed may have malfunctioned.
Ye and her friend, 16-year-old Wang Linjia, who also died, were students at Jiangshan Middle School in Zhejiang, an affluent coastal province in eastern China, according to Chinese state media. They were part of a group of students and teachers from the school who were heading to summer camp in Southern California.
The other victim, 15-year-old Liu Yipeng, later died at a hospital.
The Associated Press contributed to this report.