Don Messick voiced Scooby-Doo in the original Scooby-Doo series.
Messick supplied Scooby’s distinctive voice in Scooby-Doo, Where Are You!, which premiered in 1969. His performance combined barking, speech, nervous stammers, and comic timing, helping establish the character’s recognizable vocal personality.
Messick was a major voice actor at Hanna-Barbera and performed many animated characters across television. In the Scooby-Doo franchise, he also became closely associated with other roles, including Scrappy-Doo in later productions. That overlap can make voice credits confusing when viewers compare different series and years.
The original program had a different performer for Shaggy Rogers: Casey Kasem. Frank Welker voiced Fred Jones, while Nicole Jaffe originally voiced Velma Dinkley and Indira Stefanianna Christopherson voiced Daphne Blake in the first season. These separate credits distinguish Scooby’s original voice from the rest of the gang.