The Defence Medal 1940–1945 (Norwegian: Deltagermedaljen 9. april 1940 - 8. mai 1945/Deltakarmedaljen 9. april 1940 - 8. mai 1945) is the award rewarded to those military and civilian personnel who participated in the fight against the German invasion and occupation of Norway between 1940 and 1945.

The medal may still be awarded due to the large number of participants in the defence of Norway during World War II and the difficulties tracking down all eligible recipients.

On the obverse is the coat of arms with the inscription 9 April 1940 - 8 Mai 1945.

Above these a narrow circle with the inscription DELTAGER I KAMPEN (Participant in the struggle).

The band can be fitted with a rosette if the recipient has distinguished himself several times.