A Chicago man who won $1 million in the lottery and then dropped dead a month later was poisoned, cops say.

Urooj Khan, 46, hit the jackpot last June on a scratch-off ticket he bought at a 7-Eleven on the city’s north side, according to local reports.

The hard-working Indian immigrant, who owned three dry cleaner businesses, said he planned to donate some of the money to St. Jude’s Children’s Research hospital, pay off his debts and invest the rest in his businesses.

Several weeks later, at a ceremony publicizing his win, he told lotto officials, “Winning the lottery means everything to me.”

The actual check for nearly $425,000 was cut on July 19.

Khan died the next day.

According to police, Khan came home from work, ate dinner with his wife, Shabana Ansari, and daughter, Jasmeen, and went to bed,