Judge Matthias Kreutzberg-Kowalczyk granted an application for an injunction filed by airport operator Fraport and German airline Lufthansa against walkouts by apron control staff, who have been striking since February 16 over demands for higher pay.
The GdF union of air traffic workers said it would appeal the ruling, which obliges workers to call off industrial action that had initially been scheduled to run until Thursday.
The court had on Tuesday also banned air traffic controllers from walking off the job in support of the strikers.
Some 200 apron controllers, who direct aircraft in and out of their parking slots from the control tower and on the tarmac, have caused the cancellation of hundreds of flights a day over the past two weeks in an increasingly bitter dispute over higher pay and bonuses as well as reduced working hours.
"We will appeal both decisions," GdF chief Michael Schaefer told news agency AFP.
"But first of all, we have to halt our industrial action and we're in talks with Fraport about the resumption of work," he said.
Following an initial five days of walkouts, the 200 tarmac employees returned to work a week ago after agreeing to hold new talks with management. But those new negotiations quickly broke down amid bitter recriminations, and this week hundreds more flights have been grounded.
Fraport insists it had made concessions "on many points in the union's extremely high demands."
Fraport has said it has been able to ensure that around 80 percent of flights have taken off and landed, with domestic and short-haul flights being primarily hit by the action.
Frankfurt Airport, Germany's main hub, is Europe's third busiest after London Heathrow and Paris Charles de Gaulle, handling around 1,200 take-offs and landings daily.