Efficient lossless coding of a texture image and its corresponding depth map is important to perform accurate view synthesis in 3D applications. In this paper, a novel HEVC-based three-layer texture and depth coding method is proposed for lossless synthesis in 3D video coding. The proposed method performs lossy and lossless texture coding in the first and second layers, respectively. A quantization parameter (QP) in the first lossy coding layer is adaptively selected for each block, based on a relationship between the first and second layers. In the third layer, the lossy depth coding is performed by using synthesis-based depth coding and texture-based depth intra prediction mode. The synthesis-based depth coding technique adopts the lossy coding but guarantees zero synthesis distortion. The texture-based depth intra prediction mode performs the depth prediction by using the associated texture information. Experimental results demonstrate that the proposed method obtains higher coding performance than conventional lossless coding methods.