Krogh recorded her first album in 1970 when she was 14 and has been a fixture in Norwegian popular music since then. In 1971 she won the Norwegian Eurovision Song Contest selection, the Melodi Grand Prix, with the pop-ballad "Lykken er..." ("Happiness Is..."). On this occasion she finished second last, but 14 years later she won the Eurovision Song Contest with Elisabeth Andreasson, whom together formed the duo Bobbysocks!. She also represented Norway as a part of the quartet Just 4 Fun in the Eurovision Song Contest 1991.
Krogh has released 19 albums, including a compilation, Hanne Krogh: 40 beste in 1994, and many singles.
Krogh with Andreassen performed live in Danish capital Copenhagen for the 50th Eurovision anniversary, the Congratulations show. Another appearance of the duo was when they performed their winning melody at the city hall plaza (Rådhusplassen) in Oslo during the Eurovision concert in EuroPride 2005. She contributed to the 2011 album Mitt lille land.
Hanne also co-wrote the 1987 Norwegian entry Mitt liv for Kate Gulbrandsen.