It will be the agency’s first space mission since the 2003 Columbia disaster, in which seven astronauts lost their lives.
Shuttle program director Bill Parson said NASA engineers believe they have eliminated all possible causes of the fuel sensor failure that halted the launch.
“We have some repairs … to make on the vehicle, and we will pick up the count for the launch on Saturday … and we will proceed to a launch on Tuesday,” said Mr Parson.
The agency hopes Discovery will be launched on July 26 at 10.34am local time (12.34am AEST), from the Kennedy Space Centre near Cape Canaveral in Florida.
If shuttle fails to lift off in July, NASA will have to wait until September 9 to 24 for the next launch window.
NASA cancelled last week’s launch when a fuel sensor malfunctioned about two hours before it was due to take off, and engineers have since been working to find the cause.
Experts believe electromagnetic interference or an issue with how the sensor’s power supply is grounded to the vehicle could be the cause.
The suspect sensor is one of four that form a backup system to ensure the shuttle’s three main engines shut off before the fuel tank runs dry.
If the glitch reappears, engineers might decide to launch the shuttle regardless, as only two of the four sensors would have to register the hydrogen tank as dry.
“If it was a known failure, we might very well be willing to fly with three of the four sensors,” said Mr Parson.
NASA grounded its space exploration program after the Columbia shuttle disintegrated upon re-entry into the Earth’s atmosphere.
Discovery is scheduled to embark on a 12-day mission, during which its crew would test post-Columbia safety upgrades and deliver supplies and equipment to the International Space Station.