Canterbury Road is closed in both directions between Chapel Road and Fairford Road at Bankstown due to a crash involving a car and pedestrian.
Emergency services and traffic crews are on site.
Westbound traffic is being diverted at Fairford Road.
Eastbound traffic is being diverted at Chapel Road.
Motorists are advised to use an alternative route and allow extra travel time.
Motorists can consider using Fairford Road, the M5 Motorway and The River Road to get around the closure.
For the latest traffic information, download the Live Traffic NSW app, visit www.livetraffic.com or call 132 701.