An Uber Eats delivery worker was shot dead on his way home from a shift in East Harlem last week — and his grieving sister said he would still be alive if it weren’t for the overnight subway shutdown.

Mamadou Diallo, 32, of the Bronx, was fatally shot around 2:30 a.m. May 20 at East 125th Street and Third Avenue, cops said.

Police found him lying on the ground with a gunshot wound to his chest, and he was rushed to Harlem Hospital, where he was pronounced dead.

Mamadou’s sister, Kadiatou Diallo, 36, told The Post her brother typically took the train home from work, but couldn’t because of the shutdown from 1 a.m. to 5 a.m. amid the coronavirus crisis.

“He had to find another way because the train was shut down, so he had to take the bus,” Kadiatou said. “So he was waiting for the [Bx] 15 bus to get to the Bronx and that’s when he got shot.”

The subway shutdown — enacted for the first time in 115 years — went into effect May 6, allowing workers time to deep-clean the trains.

“I believe if the subway was working, [my brother] would have never been at that time at that place,” Kadiatou said.

Kadiatou said she was told the shooting happened during an attempted robbery — a possibility that cops confirmed they are probing.

After hearing what happened to her brother, Kadiatou said she’d advise New Yorkers out in the wee hours without subway access to be extra cautious.

“I just think everybody should be aware of who is around you and be careful whenever you are out,” she said. “But sometimes you can’t avoid these things.”

Kadiatou called her brother “a hardworking guy” and “a social man” who was looking to go back to college so he could pursue a new line of work.

There have been no arrests in the slaying.

An Uber spokeswoman said that company records show a few profiles with Diallo’s name, but none have been active in the last few weeks.

The MTA did not immediately respond to a request for comment.