In order to achieve more realistic visual effect, the texturing mapping has become a very important and popular technique used in three-dimensional (3D) graphic. Many advanced rendering effects including shadow, environment, and bump mapping all depend on various applications of texturing function. Therefore, how to design an efficient texture unit is very important for 3D graphic rendering system. This thesis proposes an advanced texture unit design targeted for the rendering system with the fill rate of two fragments per cycle. This unit can support various filtering functions including nearest neighbor, bi-linear and tri-linear filtering. It can also provide the mip-map function to automatically select the best texture images for rendering. In order to realize the high texel throughput requirement for some complex filtering function, the texture cache has been divided into four banks such that up to eight texels can be delivered every cycle. The data-path design for the filtering unit has adopted the common expression sharing technique to reduce the required arithmetic units. The proposed texturing unit architecture has been implemented and embedded into a 3D rendering accelerator which has been integrated with OpenGL-ES software module, Linux operation system and geometry module, and successfully prototyped on the ARM versatile platform. With the 0.18um technology, this unit can run up to 150 Mhz, and provide the peak throughput of 1.2G texel/s.