John "Jompa" Levén was born at the Stockholm South General Hospital. The Levén family moved to Upplands Väsby when he was 7 years old. His childhood idols were Sweet and KISS and his favorite album was the KISS live album Alive!. When he was 14 years old and not interested in anything else but hard rock, soccer and partying, his grandmother gave him his first guitar, an acoustic one. That boosted his interest for music, and he was often at home practicing on his guitar. But he wasn't always practicing. Sometimes he was out with his gang to cause trouble, both for themselves and others. "I was a brat, haha! I joined a gang that was always up to something. Just boyish pranks, though, nothing too serious."

John's first band played Status Quo songs. After that he played in different bands, but none of them had any serious ambitions. He also played soccer, and it was at a soccer match that he met Joey Tempest for the first time. Later on John got his electric guitar, a homebuilt one. "My friends always complained that I spent too much time at home playing, but it was a great guitar." Unfortunately that guitar was crushed by a friend who played in a punk band.

One rainy evening in 1981, John Levén got a visit from his friend John Norum, who told him his band, FORCE, needed a new bassist. Even though John Levén was a guitarist at the time, he accepted the offer and switched to playing the bass in FORCE. Up until that time he had been an eager motocross driver. "But when I began playing with these guys, I said to my dad that 'I want to sell the bike and buy a bass rig.' 'Why is that?' 'Because I'm gonna be a rock star.' He just laughed but I said that 'I am sure I will, absolutely!'" John didn't care so much about school, which meant that meant that he ended up with bad school marks, much like Norum. After compulsory school he was educated to be a workshop mechanic. Later he started to work as a janitor and a stores man at the same time that he played in FORCE.

In April 1981 John got an offer from guitarist Yngwie Malmsteen to join his band, Rising Force. He was so flattered that he couldn't resist the offer, so he joined the band. "It wasn't that strange, really. Yngwie was already a big name in Stockholm and I was incredibly impressed by his guitar playing." Yngwie's former bassist Marcel Jacob took his place in FORCE. John recorded a single with Rising Force, "We're Gonna Break Them All", but it was never released. John felt he didn't get along that well with Yngwie and the overall mood in the band kept getting worse. "We didn't have a good drummer. Besides I was used to being in a band with a good singer, and Yngwie wasn't that good. I started to regret that I joined the band, so I decided to leave." John couldn't have been luckier with his timing, because at the same time Marcel Jacob had left FORCE. So the two bassists simply traded places once again. The bootleg Black Star contains early Rising Force recordings with John on bass.

At the same time that FORCE participated in the "Rock-SM" contest in 1982, John had to do his military service. He didn't always get a day off to be at the competition, so often he decided to go AWOL. "Guys who wanted time off to participate in sport contests could get it all the time, but not me!" Even after FORCE changed its name to EUROPE, won "Rock-SM" and started the recording of the debut album, John's troubles with the military still weren't over. "I just didn't get a leave of absence and I had to leave without permission. When I was out in the field I had to walk three miles through the woods to get to the base, have a change of clothes and then get on my way to do the recording of the album. But you had that youth enthusiasm so you got through it." Finally, just in time for EUROPE's first tour, he was discharged from military service. "What a feeling!" When Joey was busy writing songs for the third EUROPE album in 1985, John remembered a keyboard riff Joey had written as early as 1981-82. "I said, it's fantastic. You have to write a song!" Joey decided to do it and came up with the song "The Final Countdown".

Both John Levén and Ian Haugland were supposed to play on Face the Truth, John Norum's second solo album in 1992, but for some reason that never happened. Instead John Levén formed the cover band King Siguurd together with guitarists Thomas Larsson and Anders Bojfeldt, as well as vocalist Göran Edman and drummer Hempo Hildén, who had both previously recorded and toured with Norum. After recording a couple of demos in 1994, Hempo called up Glenn Hughes and asked him if he needed a band. Glenn accepted the offer, so he hired all the King Siguurd members, except for Göran, for the recording of his new album, From Now On.... Ian and Mic Michaeli were also brought in for the recording. John, Mic and Ian were all part of Glenn's live band on his From Now On... tour, which resulted in the live album Burning Japan Live.

In 1995 John Levén made a guest appearance on John Norum's cover of the Thin Lizzy song "Massacre", which was included on the tribute album The Lizzy Songs. Levén also toured with Norum in 1995 and 1999 and appeared in the music video for "Strange Days", a single from Norum's third solo album, Another Destination. In 1996 John and Ian were asked to take part in vocalist Benny Söderberg's new project. The band was called Clockwise and released two albums, Nostalgia in 1996 and Naïve in 1998. Demos for a third album were recorded, but nothing more. Clockwise recorded a cover of the Journey song "Send Her My Love" for a Journey tribute album, but the album was never released. In 1997 John joined Brazen Abbot, a band which already included Mic and Ian. With John in the lineup, Brazen Abbot recorded the albums Eye of the Storm in 1997, Bad Religion in 1998 and Guilty as Sin in 2003. John, Mic and Ian also played on the Thore Skogman album Än Är Det Drag in 1998 and Nikolo Kotzev's Nostradamus in 2001, which was a project by Brazen Abbot guitarist Nikolo Kotzev. John also formed another band, Southpaw, which released a self-titled album in 1998.

In 2002 John took part in "The Johan Kihlberg All Star Experience" project, which recorded the song "Sweet FA", which was included on a Sweet tribute album. In 2003 John, Mic and Ian joined the project band Last Autumn's Dream and released a self-titled album the same year. However, later that year EUROPE reunited, so Last Autumn's Dream had to recruit new members. One of them was Marcel Jacob.

John Levén is currently living in Stockholm. He has two children with his ex-wife Karin Winkler, Daniel and Alex, and one child with his ex-wife Annika Törnlind, Adrian.