Resurfacing work on one of the westbound lanes of the Esplanade in St Helier will begin on Saturday.
The government said the Esplanade and Victoria Avenue would remain open in both directions, but diversions would be in place between Saturday 21 and Sunday 29 October.
Work on the area between HSBC and Elizabeth Castle Ferry Kiosk is "essential", and will improve surfaces that have not been worked on in more than 20 years.
It said the work would take place during the October half term to "minimise travel delays", and advised islanders travelling in the area to "give themselves more time for their journeys".
Those travelling from the east planning to access Patriotic Street Car Park have been advised to use Castle Street.
Access to Kensington Place and Westpark roundabout from the east will not be possible. Diversions will be in place at Rue du Galet and St Aubin’s Inner Road.