The next launch attempt for Endeavour, cancelled twice since Saturday because of the fuel leak, will take place on 11 July, NASA said.
The leak was in the same spot that halted the previous launch, in the venting system designed to carry excess hydrogen safely away from the launch pad.
The cause of the leak remains unknown.
It was the same problem that forced NASA to abandon its first attempt to launch the shuttle Discovery in March.
When Endeavour eventually does head out from NASA's Kennedy Space Center in Florida, it will help finish work on the International Space Station, which orbits 350km above Earth.
