A Bronx vagrant said he’s grateful for the roadside shelter that a group of young bicyclists finished building for him on Sunday.

Anthony Johnson, 48, says his 4-by-5-by-8-foot pad should help him stay warm this week under a bridge near the Sheridan Expressway.

“I feel grateful. This is the first time anyone has done something like this for me. It’s a blessing,” Johnson told The Post on Monday. “These young people are helping someone in need, helping someone with low self-esteem to feel better about where he is in life. You can’t ask for a kinder act.”

He added: “I’m getting settled inside. It’s warm and dry.”

The volunteers finished their project Sunday and hope the city won’t tear it down before Johnson can find a more permanent place to live.

The local bike riders who pitched in range in age from 6 to 20 and number about 150.

“For work, I do general cleaning for some of the businesses in the area. It’s the money I use to eat and stay alive. Buy clothes, that kind of thing,” Johnson said.

“I lived in Mount Kisco for 25 years. That’s where I grew up. Mostly in Westchester. I worked in restaurants, I did car prep for Nissan for a while. I had a bunch of different jobs.”

Johnson said he fell on hard times a few years ago.

“Three years ago, my family got separated. My parents and my brothers, everyone just split up and went in different directions and I was kind of left without a place,” he said.

“I’m hoping to get into an industry program. Being more rested, taking a little bit better care of myself, it helps you think straight. I want to get into an industry program that will help me get housing, also getting into a rehab is going to be big. I’ve struggled with addiction for the past 10 years. Mostly alcohol and some drugs.”

The volunteers plan to come back soon to cut a hole in Johnson’s shed and add a glass window.

“This shelter is helping me live a different life, a little bit better life,” he said.