The crash occurred near Roscoe and Reseda boulevards at approximately 6:45 a.m.
The driver of the big rig was not injured, fire officials said.
Two people in the other vehicle became trapped inside their car. One was pronounced dead at the scene, and the second was extricated from the car alive.
That second victim, described as a female adult, was transported to an area hospital in critical condition.
The cause of the crash was not immediately known.