Harald "Blåtand" Gormsson (Old Norse: Haraldr blátǫnn Gormsson, Danish: Harald Blåtand Gormsen) was a king of Denmark and Norway. He ruled Norway "de jure" while Haakon Sigurdsson ruled "de facto".
He was the son of King Gorm the Old and of Thyra Dannebod. He died in 985 or 986 having ruled as King of Denmark from c. 958 and King of Norway for a few years, probably around 970. Some sources say his son Sweyn Forkbeard forcibly deposed him.