|Name||Caninius "Canine" Dog|
|Voice Actor||Tom Kenny|
|Relatives||Cat (brother) Mom ( Their long lost Mother) Dad (Their adoptive Father) HorseDuck (Their grat-great uncle; deceased)|
Cat (Cat never let him any fun), The Greaser Dogs (sometimes)
|First Appearance||Dog Gone|
|Latest Appearence||Meat, Dog's Friends|
Caninius "Canine" Dog is one of the two protagonists in CatDog.
Dog is the more happy-go-lucky and more naïve of the two. He is also the source of clumsiness. He is a American Foxhound who is extremely ambitious when Cat or any other character convinces him to take on a task, diving right into it with full force and energy. Dog is a typical loyal dog and is easily convinced. He will believe everything he is told. His attention span is the very short and he is easily distracted by balls, garbage trucks, bones, food, and his overactive imagination. Because of his dysfunctional brain, Dog is usually the one who gets the pair into trouble. Not paying attention to Cat's warnings, his actions almost always end up with some severe consequences. Despite this, in many of the episodes, it is shown that Dog is usually the one that is more popular and athletic of the two, such as the episode when Cat and Dog both went back to school to complete Cat's last day of High School. Like Cat, Dog adores his brother and looks up to him no matter how many times Cat steers him into danger. Dog is Shriek's secret crush. Dog is the typical animal. He is often distracted with chasing shadows and chasing after tennis balls, and loves eating garbage. According to "Fistful of Mail," it showed that he is the fastest canine in Nearburg. Much to Cat's dismay, he leaves a mess everywhere he goes. According to the series finale, Dog remembers what their parents were like (ex.: "Mom's four eyes; Dad's slimy green skin.") He is also 26. Dog's catchphrase is "HI HO DIGGETY," and he usually says this when he is excited about something. He is an American Foxhound/Jack Russell Terrier mix.
Dog is a light brownish dog, with an indigo-colored circle nose, a brown spot around his left eye, buck teeth, and three hairs sticking up on top of his head. He also has a whole body with one spot on his chest with his brother Cat (one at either end of its single body).
- Dog is Cat's younger brother.
- He is allergic to lobster. In the episode "Seeing Eye Dog," when Dog told Cat that Dog is allergic to lobster, Cat shoved lobster into Dog's mouth intentionally believing that Dog isn't allergic to lobster, even though he is. After Cat Cat woke up, he felt guilty that Dog's eyelids were pink, wrinkly, and closed with yellow stuff around it. He also can't eat pecan pie as he got a condition where a tree full of pecans grew on his head according to "Dog's Strange Condition."
- Even though Dog has very low intelligence, he was able to graduate high school and get a driver's license while Cat for some reason never accomplished them until he was an adult.
- This brings up suspicion that Dog is actually smarter than he seems and is an idiot savant.
- A running joke of the series is that Dog is more commonly favored than Cat, who is hated by the town. Along these lines, Dog is much more lucky than Cat. (Perhaps because he is easier to please.)
- Dog's voice is provided by Tom Kenny, who also voices SpongeBob SquarePants in another Nickelodeon show, SpongeBob SquarePants, and other characters related to the show such as Clifford.
- In the Workforce episode, he is shown to be Prize Stuffer for Kavity Krunch Cereal.