The resurfacing of Les Banques in St Sampson's will begin on 1 June.
The work will include changes to the layout aimed at making it safer to cross the busy road near the Red Lion roundabout.
A new central refuge and illuminated bollards will be put in just south of the slipway.
Guernsey's States says that will make it easier and safer for wheelchair users, people with buggies and those with visual impairments.
Work is due to start on 1 June and take four weeks. Temporary traffic signals will be in place, and signs will be put up advising of the change of access to and from the Grand Bouet.
Motorists are being advised to expect delays throughout , and the footpath and cycle path will be closed during the final phase of the works.
Renaissance 'masterpieces' on display in Guernsey
Guernsey's airline reacts to reduced demand because of Iran attacks
Survey reveals scale of dissatisfaction with off-island travel
Two youngsters questioned by Guernsey Police after fire at Leale's Yard
Prominent Guernsey consultant cardiologist suspended by the GMC
Guernsey FC features on Premier League social media
Law banning under-18s enter Guernsey vape shops labelled 'hypocritical'
Channel Island iPhone users struggle with age verification update
