A former high-rolling Wall Street trader popped suspected poison in his mouth and died moments after he was convicted of torching his $3.5 million mansion.

Michael Marin — who wrote a tell-all about the financial world, climbed Mount Everest and amassed a million-dollar art collection — was facing 16 years in prison when he apparently killed himself in Maricopa County Superior Court in Phoenix, Ariz.

Video shows Marin, a 53-year-old grandfather, putting something in his mouth and swigging from a sports-drink bottle seconds after the jury delivered the verdict Thursday.

His face turns red, and he coughs, goes into convulsions, and falls face first on the carpet.

He was carried out on a stretcher, but was dead minutes later.

Investigators said it would take two to six weeks for toxicology reports to confirm whether Marin killed himself.

The former Mormon missionary had amassed a fortune in the ’80s and ’90s as a Wall Street derivatives trader and held senior posts with Merrill Lynch and Salomon Brothers.

He left finance in 1997 after being fired from Lehman Brothers, then wrote a book that claimed to reveal how Wall Street plundered Asian markets.

After the breakup of his marriage, Marin in 2004 bought a 10,000-square-foot mansion with four-car garage in Phoenix.

But his fortune evaporated as the economy soured in 2008. In a year, his bank account went from $900,000 to $50.

Investigators said he had a monthly mortgage of $17,250 and was facing a $2.3 million balloon payment when a fire gutted his home on July 5, 2009.

Marin escaped the fire by climbing down a rope ladder, wearing a scuba tank and diving mask. Arson investigators found gasoline and dozens of phone books that fueled the flames in the home.