Sundström participated in Melodifestivalen 1999 with the girlgroup Ai with the song "Bilder av dej". The same year she started working for SVT and hosted the musicvideo show "Voxpop" for several years and she also hosted Melodifestivalen 2001. Sundström was the Swedish commentator during the Eurovision Song Contest 2013 broadcast on SVT. Josefine Sundström was the Swedish spokesperson at Eurovision Song Contest 2001 and announced the countries voting result.
Sundström is also an author having released two books Vinteräpplen in 2010 and Boel och Oscar in 2012.