Nine inspectors expected to monitor dismantling of nuclear weapons programme.
The visit will be the first time in nearly five years that North Korea has received a formal inspection from the IAEA.
Monitors from the watchdog agency were expelled in late 2002 shortly after the latest nuclear standoff began.
North Korea has said it would be willing to shut down the Yongbyon reactor once it receives an initial shipment of oil under the February deal.
South Korea, which is shipping the oil, said the shipment is expected to arrive on Saturday in the North.
|The Yongbyon plant is thought to have made
enough plutonium for about 12 bombs [EPA]
The return of the IAEA inspectors has raised expections that after months of deadlock and delay, the North may be about to make its first move to scale back its atomic weapons development.
Since 2002 North Korea is though to have used the Yongbyon plant to produce enough plutonium to make around a dozen bombs.
What will happen to that plutonium stock pile has so far not been addressed.
On Tuesday South Korea said a fresh round of six-nation talks would be held in Beijing to discuss how to push forward the process of shutting down North Korea‘s nuclear programme.
However China, which is hosting the talks, has yet to make any formal announcement.