The former Welsh government minister, who was suspended last week after allegations were made over his conduct with women, was found dead on Tuesday.
Sargeant, 49, a member of the Welsh Labour Party, told local media earlier this week that he wanted an urgent investigation into the allegations "in order to allow me to clear my name".
In a statement, police said: "At approximately 11.30am today North Wales Police were called to a report that the body of a man had been found at an address in Connah's Quay.
"The man has been formally identified as ... Carl Sargeant. North Wales Police are not treating his death as suspicious."
Welsh First Minister Carwyn Jones said in a statement: "Carl was a friend as well as a colleague and I am shocked and deeply saddened by his death."
No further details were immediately available on the nature of Sargeant's death.
He was elected to the devolved Welsh Assembly in 2003 to represent Alyn and Deeside in northeast Wales and served as environment minister and Labour's chief whip.
A statement from Llywydd of the National Assembly for Wales, Elin Jones AM reads:
“I am deeply shocked and saddened to hear of the death of Carl Sargeant AM. He served the people of Alyn and Deeside with pride and determination and he made an enormous contribution to the development of this democratic institution.
“As a mark of respect to Carl, there will be no Assembly business today. We will all want to gather our thoughts before paying proper tribute to him over the coming days. On behalf of all the Members and those who work at the National Assembly for Wales, I would like to express my deepest sympathy to his family and colleagues.”
Enter a name and e-mail address and we will e-mail this website link too them.