Does the giraffe have any predators?

Yes and No.

Due to their sheer size, adult Giraffe's are not vulnerable to predators like leopards, hyenas, wild dogs etc. However, large lion packs headed by large Adult Male lions have been known to hunt down a full grown giraffe. But, this is very rare. On the other hand, calf's are very vulnerable to predators. A lion pack can easily kill a giraffe calf or even an adolescent. Hyena and wild doc packs too are known to prey on giraffe calves.