Facial fat grafting is a key procedure in aesthetic surgery, offering rejuvenation and natural results. Success depends on precise fat placement in specific facial layers to ensure aesthetics and avoid complications like intravascular injections, which can cause severe consequences. Understanding facial anatomy is critical for surgeons, as recent studies reveal a complex layered structure. Traditional five-layer anatomy is now expanded to include the skin, superficial fascial system, and deep fascial system, specific to each facial region. This chapter serves as an anatomical guide, detailing the layers and structures of the temple, forehead, infraorbital, midface, lips, jawline, and chin regions. Accurate knowledge of these layers enhances the safety and effectiveness of fat grafting, emphasizing the importance of injection techniques and anatomical variations to minimize risks and improve outcomes. Biomechanical considerations, such as tissue mobility and stress distribution, also play a crucial role in achieving optimal results.