District Judge Royce Lamberth's order comes 10 days after he ruled that President Donald Trump's pick to oversee mass layoffs at VOA was unlawfully appointed, rendering the job cuts invalid.
Kari Lake, a former TV anchor, slashed jobs and funding after she was appointed by Trump to head the US Agency for Global Media (USAGM), which runs VOA, Radio Free Europe, Radio Free Asia and other stations.
Lamberth, an appointee of Republican president Ronald Reagan, ordered the reinstatement by March 23 of 1,042 VOA employees who have been on paid administrative leave for the past year.
The judge also ordered USAGM to come up with a plan by next week to resume international broadcasts.
VOA was created in the wake of World War II as a key instrument of American soft power worldwide.
Trump frequently attacks media outlets and denounced the editorial firewall at VOA that prevents the government from intervening in its coverage.
Three VOA employees who filed a lawsuit seeking to reverse Lake's moves welcomed the judge's ruling.
"We are eager to begin repairing the damage Kari Lake has inflicted on our agency and our colleagues, to return to our congressional mandate, and to rebuild the trust of the global audience we have been unable to serve for the past year," they said in a statement.
The Trump administration has said it plans to appeal the judge's previous ruling that Lake's appointment was unlawful.