The 18-year-old singer, who recently split from girlfriend Selena Gomez, is keen to date proper, grown up girls, reported Showbizspy.
"He doesn't just want the attention of little girls anymore," a source said.
Friends believe Bieber's immaturity played a big part in his split from Gomez.
"Justin is super needy and can be a big baby around Selena. It is hard for him to make real friends because he likes the temporary attention of strangers, but didn't see how it hurt Selena.
"Selena didn't feel Justin was respectful of their relationship. She was constantly catching him in positions with other girls that would make her uncomfortable. She would get super jealous," the source added.