The crash occurred at 5:10 a.m. Sunday on the eastbound freeway at the Polk Street off-ramp, according to the California Highway Patrol.
The victim was pronounced dead at the scene. Firefighters and paramedics assisted CHP with extracting the body from the wreckage, the Los Angeles Fire Department said.
"This incident will significantly impact traffic and drivers are advised to seek alternative routes," LAFD spokeswoman Margaret Stewart said.
A Sigalert issued at 5:35 a.m. closing all eastbound lanes for approximately three hours -- diverting traffic at Roxford Street -- was canceled at 9:34 a.m., the CHP said.