Ace of Diamond is a Japanese baseball-themed manga series written and illustrated by Yuji Terajima. It was serialized in Kodansha's shōnen manga magazine Weekly Shōnen Magazine from May 2006 to January 2015, with its chapters collected in 47 tankōbon volumes. A sequel titled Ace of Diamond Act II was serialized from August 2015 to October 2022, with its chapters collected in 34 tankōbon volumes.