Hamza Bin Laden, the son of al-Qaeda founder Osama Bin Laden, died in an air strike, US media outlets reported citing intelligence officials.
The place or date of death were unclear. The Pentagon did not comment.
Bin Laden, thought to be aged about 30, had released audio and video messages calling for attacks on the US and other countries.
As recently as February, the US government offered $1m (£825,000) for information leading to his capture.
His death was widely reported by US media outlets including NBC News, the New York Times and CNN, citing unnamed US intelligence officials.
There was no confirmation from al-Qaeda.
The reports said Bin Laden was killed in a military operation in the last two years and the US government was involved, but the exact date and time were unclear.
President Donald Trump declined to comment when questioned by reporters on Wednesday, as did the White House national security adviser John Bolton.
Bin Laden had urged jihadists to avenge his father’s killing by US special forces in Pakistan in May 2011.
In 2018, in his last known public statement, he called on the people of the Arabian Peninsula to revolt. Saudi Arabia stripped him of his citizenship in March.