The body of M Krishnan, who died two weeks ago while in police custody, arrived at Universiti Malaya Medical Centre (UMMC) at 10.19am for a second-mortem.
The post-mortem will be led by Dr K Mathiharen, the hospital's Pathology Unit head.
It is expected to start shortly, after P Revathi re-identifies her husband's body, followed by a short briefing from Dr Mathiharen.
Also present to witness the post-mortem are the lawyers representing the family, N Surendran and Gurmit Singh Hullon.
Krishnan, 37, a wireman, was arrested on Jan 2 at the Taman Miharja condo, Cheras with four others for alleged drug possession.
However, homemaker Revathi, 37, has disputed that her husband was involved in drugs.
On Jan 7, Krishnan, a father of six children aged between eight and 17, was found dead in the lock-up at Bukit Jalil police station.
Two days ago, both the police and the attorney-general allowed the family's request for a second post-mortem in a settlement recorded before High Court judge Mohd Zabidin Mohd Diah.
The first post-mortem, that was also conducted at HUKM, cited complications related to a stomach ulcer as Krishnan's cause of death.
However, his family claimed that the victim's body was covered with bruises, as well as a wound caused by an open cut on his right abdomen and a contusion on his right eye.