Hundreds of runners will line up in Church Street for the race which gets underway at 9am.
Roads that will be closed as the runners make their way around the course include Church Street, Morda Road, Nant Lane, Trefonen Road, Oswestry Road and Upper Brook Street.
Race organiser Alan Lewis, from Adrenaline Events, said many road sections would only be closed for a short period.
"If you live on the route and will need to leave by car during the road closure we advise that you move your car before the closure starts at 8.15am," he said.
"If you are travelling into the town, please follow the diversion routes to avoid the closed roads.
"The race will take place on fully closed roads for the safety of the runners and the volunteers."
Mr Lewis urged runners and spectators to support the town of Oswestry by enjoying the eateries and shops during the day.
He said people of all abilities had signed up for the race, with a generous cut-off time for completion to allow slower runners to finish.
The charity partner for the event is Hope House Children's Hospice, which the runners pass on the route.