She is voiced by Catherine Keener.
Grug's mate. She's every bit as solid and sure as Grug, but over their many years of raising their children together, Ugga has always deferred to her husband's aurthority. When she suddenly finds herself in the position of being a cave-wife with no cave, Ugga is forced to make the right decision for her family -- even if that means changing the way they live.
Ugga is more open-minded than Grug. She understands why Eep wants to leave the cave and tries her best to cheer Grug up because of her independence.
Later on in the film , she has her own idea, and uses it to protect herself, her mother, and her baby girl Sandy from giant carnivorous flowers. This is a turning-point for Ugga as she literally and figuratively starts letting her hair down and puts the old ways her family followed (Never leave the cave! New is always bad; never not be afraid) behind her. She also starts to fight with Grug and tells him to stop being such a drag.