Mr. Garrison Senior is Mr. Garrison's father from Arkansas. He first appeared in the Season Three episode "World Wide Recorder Concert", and made a brief cameo appearance in the Season Twenty episode, "Oh, Jeez".
In "World Wide Recorder Concert", Herbert Garrison is in town visiting, and confronting some unfinished demons he has with his father. Garrison believes that his father didn't love him, because he never sexually abused him. In the end, Mr. Garrison Senior and Mr. Garrison reconciled, with the help of Kenny G, much to the joy of Mrs. Garrison.
Mr. Garrison Senior is a burly, square-jawed senior citizen who wears blue work overalls with a red-outlined nametag with an orange long-sleeved shirt underneath when working at his gas station.
At home or at his local bar, he wears his orange, long-sleeved top with a dark-green overcoat and dark brown trousers and black shoes. He has age lines on his face, and gray-white hair swept back.
Mr. Garrison Senior is a hard-working man, as he owns and runs his own gas station despite clearly being past the retirement age. Unlike the rest of his family, he has quite a normal moral compass. He becomes shocked in "World Wide Recorder Concert" when his son, and later his wife, became angry with him because he never sexually molested his son as a child.
Confused, but wanting to help his son, he reluctantly asks his drinking buddies for advice at his local bar, but they mistake his question as a "scruples" riddle and get distracted asking each other different riddles. Frustrated, he uses his own initiative and arranges for the musician Kenny G to have sex with Mr. Garrison, pretending to be him. He tries to pay him for his services, but to his surprise Kenny G refuses to take the money.
- "World Wide Recorder Concert" - Seen consoling her son about the lack of sexual abuse by his father.
- "Oh, Jeez" - Cameo; seen in a photograph.