Donphan is a gray, proboscidPokémon with a thick, black band of hide running down the length of its back and extending to the tip of its long trunk. When this Pokémon curls up, the band resembles a car tire. This tough hide prevents regular attacks from inflicting even a scratch. A pair of white tusks, which are smaller on the female, extend from the corners of its mouth. It has thin, elongated ears held out almost perpendicular to its body. Its four short legs are each encircled with a broken, black band and have three toes.
Donphan has the ability to curl up into a ball and violently roll around like a wheel. These rolling tackles are strong enough to knock down a house. While normally calm, Donphan can become enraged and start a rampage. Once it starts its rampage, it will be almost unstoppable. Donphan will chase after anyone who angers it. The anime shows that this ability is further used as a form of courtship. The male Donphan have rolling competitions to demonstrate their toughness to the females. A Donphan's tough hide is so strong, not even a car can scratch it. Despite this, the armor is extremely vulnerable to rain.
It has been demonstrated that Donphan has a keen sense of smell, capable of sniffing out a gem known as amberite. Donphan travels in herds with a ranking system. The larger its tusks, the higher its rank in the herd. It lives in rough, mountainous terrain.
Both Great Tusk and Iron Treads share a resemblance to Donphan. Great Tusk is theorized to be Donphan's ancient ancestor from the dinosaur era, while Iron Treads is believed to be a descendant of Donphan or a scientific weapon sent to the Pokémon world by aliens.
Donphan shares its category with Tyranitar. They are both known as the Armor Pokémon.
Donphan and Ursaring, along with their pre-evolved forms, are the only Pokémon to swap version-exclusive status between localizations. While Phanpy and Donphan are found only in the Japanese and Korean Gold, they are not found in Gold in other languages, being found in the Silver Version of those languages instead, with Teddiursa and Ursaring getting the opposite treatment. This is changed in the remakes HeartGold and SoulSilver, where they follow the Japanese and Korean Gold and Silver.
Donphan seems to be based on an adult elephant, possibly the pygmy elephant or the extinct dwarf elephant due to its relatively small size (if compared to Copperajah). The ridges on its dark gray backside are similar to tire treads, causing it to resemble a spinning car tire when using its Rollout attack. Its armored body may be a reference to war elephants that were trained by humans for combat. Donphan's Ground type may come from the fact that elephants like to play in mud or that tyres always stick to the ground and are made out of rubber which is known as a great insulator fitting the Electric-type immunity.
Donphan and Donfan may be a combination of don (Spanish for lord or master) or -don (common suffix in names of prehistoric animals derived from the Ancient Greek word for tooth) and elephant.