Improvements are being made to make the station forecourt clearer and safer for pedestrians, cyclists, taxis and motorists.
A new cycle route will be created between the station and the city centre, while an existing cycle link from the station to Westgate Leisure Centre will be upgraded.
Pedestrians will find it easier to cross between the station entrance (near the Globe pub) and the level crossing on Stockbridge Road.
West Sussex County Council is carrying out the work – to start on Monday 3 November - to make it easier for people to travel by bike or by foot and for passengers to move between the railway and bus stations.
County Council Cabinet Member for Highways and Transport, Pieter Montyn, said: “This work will make it much clearer and safer for people to cycle and walk around the city.
“There will be clearer signs for motorists and taxis when they arrive at the station to pick up or drop-off passengers.”
He added: “There are further improvements to cycle routes in Chichester planned next year, at Northgate and along a circular route for the entire city.
“By the spring we expect cycling around Chichester City Centre to be an appealing alternative to travelling by car.”
The work is expected to last for five weeks and disruption is likely.
Motorists are encouraged to use the southern forecourt to pick up and drop of passengers.
The taxi rank and disabled parking bays on the northern side of the station will be temporarily relocated elsewhere within the station car park for the duration of the works.
Traffic management will be in place to limit access to the northern side of the station.