The mammals of Wilpattu are one of the biggest attractions for visitors at the park, with around 41 species, including 4 of them being endemic to Sri Lanka (The Toque Monkey, Purple-faced Leaf Monkey, Sri Lanka Golden Palm Cat and Mouse Deer). You can find many mammals during the day, including the Spotted Deer, Barking Deer, Sambar Deer, Wild Buffalo, Jackal, Porcupine, Wild Boar and the fast-moving Black Naped Hare that hop in the open grasslands. Nocturnal species such as slow moving Grey Slender Loris prowl silently looking for their pray, while smaller carnivorous mammals are swift and hard to find. Jungle Cat, Rusty Spotted Cat, Fishing Cat, civets and mongoose species require a keen eye to locate and are found more frequently in the early mornings and evening hours.
A colorful Painted Bat (Kerivoula picta) had been recorded near the villu habitats of Pomparippu and other insectivorous bat species are present in the abandoned buildings of the park premises.
The Sloth Bear can be seen alone or traveling with cubs, foraging for berries and termites; while other larger mammals like the Barking Deer, herds of elephants and fearless leopard can be seen during day.