The 68-year-old man from Lancing was taken to hospital with serious head injuries following the incident on the Broadway, in Lancing, at 10.30am on Saturday.
Emergency services were called to the scene, and the man was taken to the Royal Sussex County Hospital in Brighton with serious head injuries.
He died on Monday morning.
The Broadway was temporarily closed both ways following the accident, before being reopened on Saturday evening.
Police are now appealing for witnesses.
Anyone who saw what happened is asked to email [email protected] or call 101 quoting Operation Lanrick.
Don’t miss out on all the latest breaking news where you live.
Here are four ways you can be sure you’ll be amongst the first to know what’s going on.
1) Make our website your homepage at www.worthingherald.co.uk/
2) Like our Facebook page at www.facebook.com/Worthing.news
3) Follow us on Twitter @Worthing_Herald
4) Register with us by clicking on ‘sign in’ (top right corner). You can then receive our daily newsletter AND add your point of view to stories that you read here.
And do share with your family and friends - so they don’t miss out!
The Worthing Herald - always the first with your local news.
Be part of it.