The two-stage vehicle, which has been developed with the assistance of Russia, will blast off from the Naro space complex, 475km south of Seoul.
The rocket, named the Korea Space Launch Vehicle-1 (KSLV-1), will seek to place in orbit a 100kg satellite.
The event will be monitored by rival North Korea, which has been criticised by the international community for pursuing its own rocket programme.
Earlier this year, the North announced that it had successfully orbited a satellite of its own; but the claim was dismissed by the US, Japan and South Korea who called the April flight a cover for a test of ballistic missile technology.
The KSLV-1 launch is scheduled to take place between 0740 and 0920GMT.
The rocket is 33m long and weighs some 140 tonnes. Its Russian liquid-fuelled first-stage is said to produce 1,700 kilonewtons of thrust at launch.
The second stage, which burns a solid fuel, was produced by South Korean engineers. It is intended to generate 80kN of thrust and is designed to place the Earth observation satellite into its final orbit.
South Korea wants to develop an advanced space programme to compete with other Asian space-faring nations - China, Japan and India.
It has already launched 10 indigenously produced satellites on other countries' rockets.
In April last year, Seoul sent its first astronaut into space aboard a Russian Soyuz rocket.
Yi So-Yeon spent 11 days on the International Space Station (ISS), carrying out experiments for the government and industry.
