It happened at its junction with the Stewartstown Road.
Sinn Féin MLA Jennifer McCann has expressed her condolences.
She said: “The local community is shocked and saddened by the death of a man in a crash at the McKinstry roundabout in West Belfast.
“I would like to express my sympathies to the family and friends of this man.
“I would also take the opportunity to praise the actions of local people who tried to help the man until emergency services arrived.
“Every death on our roads is one too many. Sadly this is the third in one day. I would encourage all road users to exercise care and caution on the roads at all times.”