The cannons, weighing half a ton each, will be hoisted into place at the base of the Nelson Monument in the centre of Castle Green early this Friday morning September 2.
They will be brought to the site on a low trailer from Rotherwas where they are in temporary storage and then hoisted into position using a transporter with a telescopic arm.
Previously there were four cannons at the base of the monument, one mounted at each corner.
One cannon, nicknamed "Roaring Meg", can now be found at Goodrich Castle.
As part of the overall improvement scheme for Castle Green the two cannons, which were also once located at the front of Churchill House in Hereford’s Venns Lane, have recently been restored by the English Heritage workshop at Atcham and will be relocated at the two south facing corners of the monument.
The Monument itself has also recently received a partial makeover.
The square plinth has been cleaned, missing stones replaced and all open joints repointed by specialist company C D L Stone Restoration.
The works have been overseen by Herefordshire Council's Property Services Department and Conservation Section with Herefordshire Jarvis Services undertaking the groundworks and fencing erection.
Noel Knight, Historic Building Surveyor said: "I am delighted that after several years of planning, essential repairs to the base of the monument combined with the erection of railings around its base are to be completed.
“These will be complemented by the return to Hereford of the pair of cannons.
“Additionally, with the bicentennial celebrations of Trafalgar in October, both the timing and completion of this work could not be more appropriate."
In addition, railings similar in design to those at the west end of Castle Pool have been specially made and placed around the base of the monument being mounted on a low replica Bath stone wall, similar to the original layout that can be seen in photographs taken around 1900.
The railings, yet to be painted Trafalgar Blue, will all be ready well in time for the Bicentenary celebrations of that famous sea battle in October.