Arsinoitherium's most distinctive feature was the two large horns on their snouts. The horns were hollow and possibly used to produce loud mating calls as well as to compete with rival males. Arsinoitherium was a hefty creature with thick, hairless skin resembling elephant hide.
Arsinoitherium was very selective in the types of fruit and leaves it ate. Its size meant it had to eat a lot of food - it probably spent much of its day chewing on something.
Arsinoitherium lived in small groups and would have been in the water most of the time. It couldn't straighten its legs, suggesting they were better for wading and swimming than for walking. Its large size kept it safe from most predators, although creodonts might tackle a young Arsinoitherium.