Over the next few years Forest Enterprise Scotland will plant them around Loch Trool and the Cree Valley.
It is hoped the acorns should help to grow about 600,000 young trees creating a "large and vibrant habitat".
Environment forester Gareth Ventress said that as soon as they had seen they were in for a "bumper crop" of acorns they began planning to collect them.
"We also decided to get help from other staff throughout Scotland and asked them to collect acorns from other native oak woods found on the national forest estate," he said.
"The Cree Valley Community Woodland Trust, Borders Forest Trust and Moffat Community Woodlands all assisted in the big collection too in order to further native woodland expansion across their project areas in south Scotland.
"By combining acorns collected from across Galloway Forest Park, we increase the genetic diversity of the trees linking the remnant woodlands.
"This is vital for creating robust and resilient woodlands that can handle pests and diseases well into the future."
The acorns are collected by laying huge felt nets across the forest floor in order to keep them off the soil and make collection easier.
Once the acorns are collected they are sorted then stored.
Over the next three to four years the acorn seeds will be germinated and grown so that saplings can then be planted but many of the seeds will be "graded" out and deemed infertile during this period.
About 600,000 saplings are estimated to be likely to be produced from the acorns.
These young trees will help create new oak woods and "enrich the woodland habitats" throughout Galloway Forest Park.
More than one million acorns have been collected to help expand ancient oak woods in the Galloway Forest Park.