At about 7:40 a.m., police received a call about a collision at Park Avenue and McEvoy Street.
Officers arrived to find the Pontiac Firebird lodged under the big-rig's trailer.
The 10-year-old girl was okay, according to witnesses, but was taken to the hospital to be checked out.
Horrible crash on Park Avenue in San Jose. Firebird slides under bed of semi-truck. Driver of Firebird dies. 10 yr old passenger survived. pic.twitter.com/RuEgl3U7lH— Matt Keller (@MattKellerABC7) March 31, 2017
The adult victim, who was driving the Pontiac Firebird, was pronounced dead at the scene, according to police.
Police say the driver of the big-rig turned left from westbound Park Avenue onto McEvoy Street, and that's when the Firebird, driving eastbound, slammed into the bed of the semi-truck.
A witness tells ABC7 News he jumped into action when he saw the young girl.
"She was distraught. She was bloody. She was flung over the seats saying my daddy's dead. My daddy's dead. And I calmed her down by saying breathe deeply, breathe slowly," said Don Baker.
"I was just informed that her condition and injuries are non-life threatening. It appears that she will be fine. Just a little shaken up," said Albert Morales, with the San Jose Police Department.
The big rig driver stayed at the scene after the collision and is cooperating with investigators, police said.
The crash is San Jose's 11th fatal collision of the year.
The Bay City News contributed to this report.