Billberg may refer to:

• Gustaf Johan Billberg (1772–1844), Swedish botanist and entomologist
• Rolf Billberg (1930–1966), Swedish alto saxophonist

• Karol, Gujarat
• Karol Gwóźdź
• Karol Henry
• Karol Hochberg
• Karol Hoffmann (athlete, born 1913)
• Karol Hoffmann (born 1913)
• Karol Hutten-Czapski
• Karoli, India
• Karoliine Hoim
• Karoliine Hõim
• Karoli, Michael
• Karolina Bednarova
• Karolina Bosiek
• Karolina Ciaszkiewicz
• Karolina Fotiadou
• Karolina Goliat
• Karolina Hajkova
• Karolina Halatek
• Karolina Henry
• Karolina Hájková
• Karolina Jagieniak
• Karolina Juszczykowska
• Karolina Karlsson
• Karolina Kochaniak
• Karolina Koleczek