|Played by||Robert Jennings|
|First Appearance||Grapefruit's Revenge|
Grandpa Grapefruit is an elderly grapefruit and is a character who appeared only in Grapefruit's Revenge. He wanted to avenge Grapefruit's death along with Grapefruit's Sister and Grapefruit's Second Cousin. Grapefruit's Grandpa was mentioned again in Food Court, where Grapefruit's Nephew was testifying against Orange.
Depicted as an old grandfather, Grapefruit's Grandpa wears a cowboy hat and has a white mustache with a beard. He has a country-style/geezer accent.
- He is the first elderly character in the series.
- It is unknown if he died or not as he was only seen alive.
- It is uncomfirmed if he is Grapefruit's paternal or maternal grandfather.
- He is the fourth grapefruit in the series.
- Like Grapefruit's Second Cousin, he is a grapefruit with facial hair.
- "And I'm Grapefruit's Grandpa. I'm here to avenge his death,"
|Characters of The Annoying Orange|
|Main Characters||Orange · Pear · Midget Apple · Marshmallow · Passion Fruit · Grapefruit · Grandpa Lemon · Apple|
|Recurring Characters||Squash · Knife · Liam the Leprechaun · Captain Obvious · Nude Dude · Dr. Bananas · Zoom · Copper Lincoln · Lou the Tick · Orange's Sister · Gaming Grape · Sour Rangers (Red · Yellow · Pink · Green) · Mustachios|
|TV Exclusive Characters||Nerville · Apple · Coconut · Peach · Tomato · Banana · Pineapple · Ginger · Broccoli Overlord|