This man’s wife takes “till death do us part” seriously.

A retired media exec is being sued by his ex-mistress for refusing to leave his wife — who told him she’d rather “see them bury you six feet under” than let him go, according to a Manhattan lawsuit.

And because the scorned other woman couldn’t have her man, she wants $2 million instead.

Theodora Lee Corsell, 67, is suing James Greenwald, 88, for six years of unpaid work and because he wouldn’t cross his angry wife.

“According to Greenwald, [his wife] Marilee told him, ‘I will see them bury you six feet under before I grant you a divorce. I’m the last Mrs. Greenwald,’ ” Corsell recounts in court papers.

The retired fund-raiser from the Upper East Side says she was both professionally and romantically involved with Greenwald, although he continued to live with his 77-year-old second wife on Park Avenue amid the six-year dalliance.

Greenwald headed Katz Communications, a national TV and radio sales advertising company, in the 1970s through the 1990s.

Corsell was Greenwald’s glorified gofer over the last six years. She handled everything from getting rid of unused New York Giants tickets to promoting his unpublished memoir. She even helped him quash a $3 million threat by one of Greenwald’s other mistresses — who planned to out him to his wife, ­according to court papers.

Then she zeroed in on getting him divorced.

Corsell, by her own admission in court papers, dug up information on Marilee’s telephone calls and purchases, but the work was all for naught.

Greenwald’s attorney, Steven Mintz, said his client “remains happily married to his wife” and called the suit a “shameless shakedown.”

His co-counsel, Alton Abramo­witz, declined to address the specific allegations in Corsell’s lawsuit.

Corsell’s suit says Greenwald’s other mistress, identified as Ms. X in court papers, was demanding he leave her $3 million in his will because he made $300 million off the sale of Katz.

For all her hard work, Greenwald promised Corsell, “I owe you everything and I will compensate you,” her suit says.

She’s tagged the “reasonable value” of her “services” at $2 million.

She claims she’s due the money because her “professional services . . . were separate and apart from . . . the parties’ romantic relationship.”