A lorry, a van and three cars collided on the southbound carriageway at about 09:13 BST.
The motorway was shut between junction five, for Castle Bromwich, and six, for Spaghetti Junction. It has now been fully reopened.
The van driver died at the scene. The lorry driver sustained injuries to his neck and chest.
An air ambulance was sent to the site of the crash, West Midlands Ambulance Service (WMAS) said.
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Paramedics found the van driver in cardiac arrest and with serious injuries at the side of the road.
"The lorry driver, a man believed to be in his 40s, was treated for neck and chest injuries and taken to Heartlands Hospital by land ambulance," a WMAS spokesman said.
Drivers faced diversions and long delays during the disruption.
One man has died and a second taken to hospital after a crash on the M6 which closed both carriageways.