HeadStudio is a novel framework that generates realistic and animatable 3D head avatars from text prompts using 3D Gaussian Splatting (3DGS). The framework combines an animatable head prior model, such as FLAME, with 3DGS to enhance texture and geometry modeling. It improves the optimization process through super-dense Gaussian initialization, animation-based text-to-3D distillation, and adaptive geometry regularization, enabling joint learning of shape, texture, and animation. Extensive experiments demonstrate that HeadStudio produces high-fidelity and animatable avatars with real-time rendering, outperforming state-of-the-art methods. The framework is efficient, requiring only 2 hours of end-to-end training on a single NVIDIA A6000 GPU to generate 40 fps avatars. HeadStudio also supports real-world speech and video-driven avatars, making it suitable for applications in augmented or virtual reality.HeadStudio is a novel framework that generates realistic and animatable 3D head avatars from text prompts using 3D Gaussian Splatting (3DGS). The framework combines an animatable head prior model, such as FLAME, with 3DGS to enhance texture and geometry modeling. It improves the optimization process through super-dense Gaussian initialization, animation-based text-to-3D distillation, and adaptive geometry regularization, enabling joint learning of shape, texture, and animation. Extensive experiments demonstrate that HeadStudio produces high-fidelity and animatable avatars with real-time rendering, outperforming state-of-the-art methods. The framework is efficient, requiring only 2 hours of end-to-end training on a single NVIDIA A6000 GPU to generate 40 fps avatars. HeadStudio also supports real-world speech and video-driven avatars, making it suitable for applications in augmented or virtual reality.