This pooch doggy-paddled to safety — all the way across the Hudson River!

A puppy that got separated from his new family and jumped into the Hudson River from upper Manhattan miraculously made it to New Jersey and was then reunited with his grateful owners early Tuesday morning.

The ordeal started Saturday afternoon when owner Ellen Wolpin said she was walking with her Leonberger Bernese mix named Bear on the Upper West Side to get a better-fitting dog harness when the six-month puppy broke loose from his loose-fitting collar.

Bear, who is a seizure-service dog for Wolpin’s 20-year-old developmentally disabled son Zack, started to head back toward his home, but became startled and bolted when a bystander tried to scoop him up, she said.

From there, Bear was on the loose, running about 30 blocks on the bike trail near the water until 110th Street when he jumped into the river and started paddling, Wolpin recalled to The Post Tuesday evening.

Another bystander saw Bear begin swimming across to New Jersey, but lost sight of him about three-quarters of the way to the other side, Wolpin said.

She called 911 and patrol boats scoured the river looking for the dog, but with no luck.

“We didn’t think that he made it across, I was sick to my stomach and just kind of kept hoping that it was a nightmare,” Wolpin said. “On Sunday, I was hoping that I would get a phone call from somebody and then come Monday there’s no way this dog survived and then at 5 o’ clock this morning I got a phone call from the Edgewater Police Department that they had him.”

Edgewater Fire Company No. 1 even posted on Facebook Tuesday morning about finding a pup under a pier at Independence Harbor predawn.

“He did like a full triathlon almost,” Wolpin also said. “Because he ran about a mile-and-a-half and then swam about a mile.”

Bear was reunited with his family around 6:30 a.m., as first reported by the online news outlet I Love The Upper West Side.

Zack, who kept asking where Bear was after the dog went missing, gave his puppy a heartwarming embrace right away, Wolpin said.

Wolpin picked up a harness first thing in the morning before Bear even returned, and then later purchased a couple others just to make sure at least one of them keeps Bear at bay. Bear was also brought to the veterinarian for a check-up where he was given a clean bill of health.  

“We were so happy,” Wolpin said, whose friends keep telling her it’s a Christmas miracle. “This dog has had tons of treats and tons of hugs and we’re just doing everything possible.

“But the first thing we did was give him a bath.”