A spokesperson said a traffic management plan will be in place, however delays and diversions are anticipated across Belfast from Saturday morning through to the evening and motorists are advised to leave extra time for their journey.
Chief Superintendent Darrin Jones, Belfast Area, said: “This is a big event with up to 25,000 people expected to take part.
“We are also anticipating large numbers of spectators along the route.
“We are asking everyone who is planning on travelling through Belfast on Saturday to plan ahead and leave extra time for their journeys.
“We will have traffic diversions and management in place and would ask all visitors to the city to be patient and follow the instructions of marshals and our officers.
“Coaches will have limited time to undertake pick-ups so it is essential that participants go directly to their pick-up point. We will be on the ground to assist.
“We want everyone visiting the city on Saturday to have a safe and enjoyable day so please work with us and be considerate and respectful of all those around you,” he added.
Meanwhile, Translink has advised bus passengers in Belfast to leave extra time for their journeys and expect diversions and delays due to road closures and traffic restrictions during the parade.
A Translink spokesperson said: “For anyone attending the event there will be continuous shuttle bus services arranged by the Grand Orange Lodge of Ireland, operating between Stormont and Chichester Street approx. every 20 minutes.
“Extra capacity will also be provided on rail services, with more six car trains in operation. Additional relief services will also operate subject to demand.
“Follow the latest travel updates at www.translink.co.uk , on our Journey Planner app or @TranslinkNI.”