Bieber's partying, pot smoking and drinking is out of control and Braun is extremely worried about the 19-year-old, one source told Radar.
"Justin is hanging out with the wrong people," the source close to the star told Radar. "It's been one incident after another with him and Braun has always been very supportive and still is.
"But now Scooter wants him to go to rehab to get his act together. Justin needs to get away from the bad influences in his life."
Bieber has been smoking a lot of pot, drinking and been involved in numerous incidents. His neighbors are furious at his party lifestyle, and he posted a video Friday where his giggling behavior let to rampant speculation that he was high.
Justin's mother and other close friends are also concerned about him, a source told Radar. "They all think he is surrounding himself with people who do ridiculous things," the source said.
Practically every day seems to bring a new misadventure for the teen whose image was once so squeaky clean.
"Justin needs to go to rehab for ALL of his behavior," the source said. "He needs to get control of his life again, quit smoking pot and partying. He is just surrounded by bad influences."
Braun is widely credited with guiding Bieber to superstardom. But now the Beebs has devolved into partying around the clock.
"His partying is creating problems," said the source. "Scooter is very worried about him.
"Look, everyone knows Justin is a teenager, but this is beyond that. He's got to straighten up and get away from the people he's hanging out with. That's why Scooter wants him to go to rehab.
"And he's not the only one concerned. People who have known Justin for a long time see what's going on now, see the constant partying, and they think he's headed for big trouble."