He first achieved fame as a member of the pop duo Modern Talking in the 1980s, and has since produced numerous German and international artists.

Their first single, "Hallo Taxi Nummer 10", written and produced by Tony Hendrik, was Bohlen's first record and was unsuccessful.

[citation needed] It was followed in 1981 by two other singles under that name, "Love Takes Time" and "(You're A Devil With) Angel Blue Eyes".

[citation needed] Soon after, he joined the band Sunday, with which he appeared on the ZDF-Hitparade in early 1982 with the song "Halé, hey Louise".

In 1987, the band split up and Bohlen founded his solo project Blue System, which he ended ten years later.

He also continued writing and producing for other artists, including C. C. Catch (whom he discovered), Sheree[8] (whom he signed when she was fifteen years old), and boy band Touché.

In 1986, Bohlen wrote the title song "Midnight Lady" of Tatort episode Der Tausch [de], which was performed by former Smokie singer Chris Norman and was major hit in Central Europe, topping several charts.

In 1988, he wrote the title song of Tatort episode Moltke [de], "Silent Water", which he performed himself as Blue System.

The collaboration spawned a number of successful singles, such as "Bitterblue", "Against the Wind" (which was used as the title song of Tatort episode Der Fall Schimanski [de]), and "Fools Lullaby".

In 1998, Modern Talking made a successful comeback, releasing singles such as "You're My Heart, You're My Soul '98, "You Are Not Alone", or Formula One songs "Win the Race" and "Ready for the Victory",[12] but split up again in 2003.

That same year, he published his first book, an autobiography titled Nichts als die Wahrheit, written in collaboration with Bild journalist Katja Kessler, which sold over a million copies in Germany and got a Goldene Feder.

[15] Both Nichts als die Wahrheit and Hinter den Kulissen were also released as audiobooks read by Bohlen.

He wrote and produced the entirety of the film's soundtrack, which includes the previously unreleased Modern Talking song "Shooting Star".

[24] Based on Hertin's expert assessment regarding the plagiarism allegations, the Berlin prosecutor's office initiated a preliminary investigation against Bohlen, which was dropped.

[27] He has worked with most of the winners and occasionally with other candidates, such as first season third-placer Daniel Küblböck, yielding several major hits.

Bohlen has signed numerous advertising deals with companies such as Müller Milch, Makro Markt, S.Oliver, O₂, Roller (Möbelhaus), Wiesenhof, the Deutsche Bahn, and Unilever.

[32] From 1989 to 1996, he was in a relationship with television personality and singer Nadja Abd el Farrag, also known under the stage name Naddel.

[38] Since 2006, he has been in a relationship with Fatma Carina Walz, who he met in Mallorca, Spain,[38] where one of the casting events for Deutschland sucht den Superstar was held.

According to an article by the Manager Magazine in 2018, Bohlen has a net worth of €250 million, making him one of the thousand richest Germans.