Hamza Bin Laden, the son of al-Qaeda founder Osama Bin Laden, died in an airstrike, 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.
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.
He was believed to have been under house arrest in Iran but other reports suggest he also may have resided in Afghanistan, Pakistan and Syria.
The US state department said documents seized in the 2011 raid on his father’s house in Abbottabad, Pakistan, suggested Bin Laden was being groomed to take over the leadership of al-Qaeda.
US forces also reportedly found a video of his wedding to the daughter of another senior al-Qaeda leader which was thought to have taken place in Iran. His new father-in-law was Abdullah Ahmed Abdullah or Abu Muhammad al-Masri, who was indicted for his alleged involvement in the 1998 bombings of the US embassies in Tanzania and Kenya.
Al-Qaeda was the group behind the devastating 11 September 2001 attacks on the United States, but its status has been undermined during the past decade as the Islamic State group rose to prominence.