Los Angeles police say it happened around 4 p.m. on Friday.
The victims were jewelry dealers from the Palmdale area, who were returning from selling jewelry to a store in Santa Monica.
Authorities say the robbers were able to box the victims' car in with their own before holding the couple up at gunpoint.
Police believe the jewelers were specifically targeted and are trying to figure out if they were followed or if someone knew about their dealings.
