The US State Department said it is also allowing American government workers to depart the embassy in Caracas and limiting the movement of those who stay.
An updated travel warning also urged American citizens not to travel to Venezuela due to social unrest and violence, AP reported.
The ordered departure comes three days before President Nicolas Maduro's government plans to hold a vote for an assembly tasked with overhauling the country's charter. Maduro's opposition says the election rules are rigged to strengthen his hold on power.
The US has been urging Maduro to cancel the vote and threatening more US sanctions if it occurs.