Officers arrived shortly before 5.20am on May 17 and the incident led to a temporary hold up of traffic, with the A282 QEII Bridge southbound at brought to a standstill.
Gravesend RNLI Lifeboats were also called to the incident at 5.30am.
Essex Police have today confirmed that the man was later found dead.
His family have been informed.
The police thanked the public for their patience and understanding during the emergency response.
A spokesperson for Essex Police said: “We can now confirm that, sadly, a man has died following an incident on the Dartford Crossing.
“Officers were called to concerns for someone on the bridge shortly before 5.20am yesterday (Friday 17 May).
“Emergency services attended but, sadly, a man was later found to have died. His family have been told.
“As part of our response to this incident, traffic was held for a time and we would like to thank motorists for their patience and understanding.”
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